Operating system
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Saturday, November 30, 2013
Saturday, November 23, 2013
Roll of Successful Examinees in
the
L.E.T. - SECONDARY - All Regions
Held on SEPTEMBER 29, 2013
Released on NOVEMBER 22, 2013 Page:326 of 517
Seq. No. N a m e
16201 MATUBARAN, LAARNIE BOLLER
16202 MATUBIS, JOSE MARTIN MERCIADES
16203 MATUGUINA, MA LOTIS CAPUYAN
16204 MATUGUINA, MARIE ANGELA ABELA
16205 MATUGUINAS, APRILYN VILLA
16206 MATUGUINAS, HONIE LYNNE PARACALE
16207 MATUGUINAS, JENNIFER LABABO
16208 MATULAC, GERALDINE BALLENTES
16209 MATULEN, JIMREL PARTOZA
16210 MATULIN, GERONE CASTILLO
16211 MATULLANO, JAN CONSTANTINO
16212 MATUNAN, MARIEL BANCA
16213 MATURAN, EDMAR CORANES
16214 MATURAN, JOPHET MOTLOG
16215 MATURAN, KEVIN DAN ARMENTANO
16216 MATURAN, SHAMARIE DELA PEÑA
16217 MATUS, CARMEL LOISE MONTALBAN
16218 MATUS, MARY GRACE FELISELDA
16219 MAUHAY, IRMA TUMAMBING
16220 MAULAS, ANN DRIENE SALCEDO
16221 MAUN, DAISY LAXAMANA
16222 MAURICIO, CYNTHIA MILLARES
16223 MAURICIO, DANICA BIAZON
16224 MAURICIO, LESTER DAN CUARESMA
16225 MAURICIO, MELINDA PAULINO
16226 MAURICIO, MICHAEL CABANTAC
16227 MAURICIO, MIRIEL
16228 MAURING, EMPDEL LOVE EMPAS
16229 MAURING, KAREEN MAY BAÑARES
16230 MAUSISA, HELEN JOY MONDRAGON
16231 MAUYAG, KHALID DUCOL
16232 MAUYAO, YCOFEL JOY DOTIMAS
16233 MAXCI, JONALYN COSEPE
16234 MAXIMO, JAYSON NIEVES
16235 MAXIMO, SYDNEY GONZALES
16236 MAXIMO, VAN EDWARDSON YADAO
16237 MAXINO, MARIA THERESA MARQUEZ
16238 MAY-ENG, AGNES KINFAWAN
16239 MAYANG, AILEEN CABUGAYAN
16240 MAYANGYANG, KAYCEE LACUTTA
16241 MAYBUENA, CHERYL MAY DAMICOG
16242 MAYES, JANICE ORDONIO
16243 MAYNOPAS, BENJIE DIANSAY
16244 MAYO,
ALEXANDER MENDOZA
16245 MAYO, CAREN ARRIBBAY
16246 MAYO, CATHERINE DASALLA
16247 MAYO, LERIZA MIULIO
16248 MAYO, MA BELINDA MONTAÑO
16249 MAYO, MA GLORIA LEAÑO
16250 MAYO, MARVIC REGLOS
Friday, November 22, 2013
Computer keyboard
In computing, a keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches. Following the decline of punch cardsand paper tape, interaction via teleprinter-style keyboards became the main input device for computers.
Despite the development of alternative input devices, such as the mouse, touchscreen, pen devices, character recognition and voice recognition, the keyboard remains the most commonly used and most versatile device used for direct (human) input into computers.
A keyboard typically has characters engraved or printed on the keys and each press of a key typically corresponds to a single written symbol. However, to produce some symbols requires pressing and holding several keys simultaneously or in sequence. While most keyboard keys produce letters, numbers or signs (characters), other keys or simultaneous key presses can produce actions or computer commands.
In normal usage, the keyboard is used to type text and numbers into a word processor, text editoror other program. In a modern computer, the interpretation of key presses is generally left to the software. A computer keyboard distinguishes each physical key from every other and reports all key presses to the controlling software. Keyboards are also used for computer gaming, either with regular keyboards or by using keyboards with special gaming features, which can expedite frequently used keystroke combinations. A keyboard is also used to give commands to the operating system of a computer, such as Windows' Control-Alt-Delete combination, which brings up a task window or shuts down the machine. Keyboards are the only way to enter commands on a command-line interface.
Key types
[edit]Alphanumeric
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Alphabetical, numeric, and punctuation keys are used in the same fashion as a typewriter keyboard to enter their respective symbol into a word processing program, text editor, data spreadsheet, or other program. Many of these keys will produce different symbols when modifier keys or shift keys are pressed. The alphabetic characters become uppercase when the shift key or Caps Lock key is depressed. The numeric characters become symbols or punctuation marks when the shift key is depressed. The alphabetical, numeric, and punctuation keys can also have other functions when they are pressed at the same time as some modifier keys.
The Space bar is a horizontal bar in the lowermost row, which is significantly wider than other keys. Like the alphanumeric characters, it is also descended from the mechanical typewriter. Its main purpose is to enter the space between words during typing. It is large enough so that a thumb from either hand can use it easily. Depending on the operating system, when the space bar is used with a modifier key such as the control key, it may have functions such as resizing or closing the current window, half-spacing, or backspacing. In computer games and other applications the key has myriad uses in addition to its normal purpose in typing, such as jumping and adding marks to check boxes. In certain programs for playback of digital video, the space bar is used for pausing and resuming the playback.
[edit]Modifiers
Modifier keys are special keys that modify the normal action of another key, when the two are pressed in combination. For example, <Alt> + <F4> in Microsoft Windows will close the program in an active window. In contrast, pressing just <F4> will probably do nothing, unless assigned a specific function in a particular program. By themselves, modifier keys usually do nothing.
The most widely used modifier keys include the Control key, Shift key and the Alt key. The AltGr keyis used to access additional symbols for keys that have three symbols printed on them. On the Macintosh and Apple keyboards, the modifier keys are the Option key and Command key, respectively. On MIT computer keyboards, the Meta key is used as a modifier and for Windows keyboards, there is a Windows key. Compactkeyboard layouts often use a Fn key. "Dead keys" allow placement of a diacritic mark, such as an accent, on the following letter (e.g., the Compose key).
The Enter/Return key typically causes a command line, window form or dialog box to operate its default function, which is typically to finish an "entry" and begin the desired process. In word processing applications, pressing the enter key ends a paragraph and starts a new one.
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Navigation keys include a variety of keys which move the cursor to different positions on the screen. Arrow keys are programmed to move the cursor in a specified direction; page scroll keys, such as the 'Page Up and Page Down keys', scroll the page up and down. The Home key is used to return the cursor to the beginning of the line where the cursor is located; the End key puts the cursor at the end of the line. The Tab key advances the cursor to the next tab stop.
The Insert key is mainly used to switch between overtype mode, in which the cursor overwrites any text that is present on and after its current location, and insert mode, where the cursor inserts a character at its current position, forcing all characters past it one position further. The Delete key discards the character ahead of the cursor's position, moving all following characters one position "back" towards the freed place. On many notebook computer keyboards the key labeled Delete (sometimes Delete and Backspace are printed on the same key) serves the same purpose as a Backspace key. The Backspace key deletes the preceding character.
Lock keys lock part of a keyboard, depending on the settings selected. The lock keys are scattered around the keyboard. Most styles of keyboards have three LEDs indicating which locks are enabled, in the upper right corner above the numpad. The lock keys include Scroll lock, Num lock (which allows the use of the numeric keypad), and Caps lock.
[edit]System commands
The SysRq / Print screen commands often share the same key. SysRq was used in earlier computers as a "panic" button to recover from crashes. The Print screen command used to capture the entire screen and send it to the printer, but in the present it usually puts a screenshot in the clipboard. The Break key/Pause key no longer has a well-defined purpose. Its origins go back to teleprinter users, who wanted a key that would temporarily interrupt the communications line. The Break key can be used by software in several different ways, such as to switch between multiple login sessions, to terminate a program, or to interrupt a modem connection.
In programming, especially old DOS-style BASIC, Pascal and C, Break is used (in conjunction with Ctrl) to stop program execution. In addition to this, Linux and variants, as well as many DOS programs, treat this combination the same as Ctrl+C. On modern keyboards, the break key is usually labeled Pause/Break. In most Windows environments, the key combination Windows key+Pause brings up the system properties.
The Escape key (often abbreviated Esc) is used to initiate an escape sequence. As most computer users no longer are concerned with the details of controlling their computer's peripherals, the task for which the escape sequences were originally designed, the escape key was appropriated by application programmers, most often to "escape" or back out of a mistaken command. This use continues today in Microsoft Windows's use of escape as a shortcut in dialog boxes for No, Quit, Exit, Cancel, or Abort.
A common application today of the Esc key is as a shortcut key for the Stop button in many web browsers. On machines running Microsoft Windows, prior to the implementation of the Windows key on keyboards, the typical practice for invoking the "start" button was to hold down the control key and press escape. This process still works in Windows 2000, XP, Windows Vista and Windows 7.
The Menu key or Application key is a key found on Windows-oriented computer keyboards. It is used to launch a context menu with the keyboard rather than with the usual right mouse button. The key's symbol is a small icon depicting a cursor hovering above a menu. This key was created at the same time as the Windows key. This key is normally used when the right mouse button is not present on the mouse. Some Windows public terminals do not have a Menu key on their keyboard to prevent users from right-clicking (however, in many windows applications, a similar functionality can be invoked with the Shift+F10 keyboard shortcut).
[edit]Miscellaneous
Many, but not all, computer keyboards have a numeric keypad to the right of the alphabetic keyboard which contains numbers, basic mathematical symbols (e.g., addition, subtraction, etc.), and a few function keys. OnJapanese/Korean keyboards, there may be Language input keys. Some keyboards have power management keys (e.g., Power key, Sleep key and Wake key); Internet keys to access a web browser or E-mail; and/or multimedia keys, such as volume controls or keys that can be programmed by the user to launch a specified software or command like launching a game or minimize all windows.
[edit]
Commonly used keyboard combinations
To use one of these combinations Hold the Ctrl or Alt key down and strike the letter key
Ctrl+N
Open a new word document quickly.
Ctrl+X
Cut- Removes the selection from the active document and places it on the clipboard.
Ctrl+O
Opens a previously saved document.
Ctrl+C
Copies the selection to the clipboard
Ctrl+W
Closes the active window, but does not Exit Word.
Ctrl+V
Paste - Inserts the contents of the clipboard at the insertion point (cursor) or whatever is selected.
Ctrl+S
Saves the active document with its current file name, location and format.
Ctrl+A
Selects all text and graphics in the active window.
Ctrl+P
Prints the active file, also gives the opportunity to change print options
Ctrl+F
Find - Searches for specified text in the active document
Alt+F4
Exit - Closes Microsoft Word.
Ctrl+B
Bold - Formats selected text; make text bold, or remove bold formatting
Ctrl+Z
Undo the last action. This selection can be repeated several times.
Ctrl+I
Italic - Formats selected text; make text italic or remove italic
Ctrl+Y
Redo - After an action has been undone, it can be reinstated in the document.
Ctrl+U
Underline - Formats selected text; make text underlined or remove underline
To use one of these combinations Hold the Ctrl or Alt key down and strike the letter key
Open a new word document quickly.
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Cut- Removes the selection from the active document and places it on the clipboard.
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Opens a previously saved document.
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Copies the selection to the clipboard
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Closes the active window, but does not Exit Word.
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Paste - Inserts the contents of the clipboard at the insertion point (cursor) or whatever is selected.
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Saves the active document with its current file name, location and format.
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Selects all text and graphics in the active window.
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Prints the active file, also gives the opportunity to change print options
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Find - Searches for specified text in the active document
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Exit - Closes Microsoft Word.
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Bold - Formats selected text; make text bold, or remove bold formatting
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Undo the last action. This selection can be repeated several times.
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Italic - Formats selected text; make text italic or remove italic
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Redo - After an action has been undone, it can be reinstated in the document.
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Underline - Formats selected text; make text underlined or remove underline
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Thursday, November 21, 2013
Basic Computer Terminology
active program or window - The application or window at the front (foreground) on the monitor.
alert (alert box) - a message that appears on screen, usually to tell you something went wrong.
alias - an icon that points to a file, folder or application (System 7).
apple menu - on the left side of the screen header. System 6 = desk accessories System 7 = up to 50 items.
application - a program in which you do your work.
application menu - on the right side of the screen header. Lists running applications.
ASCII (pronounced ask-key ) - American Standard Code for Information Interchange. a commonly used data format for exchanging information between computers or programs.
background - part of the multitasking capability. A program can run and perform tasks in the background while another program is being used in the foreground.
bit - the smallest piece of information used by the computer. Derived from "binary digit". In computer language, either a one (1) or a zero (0).
backup - a copy of a file or disk you make for archiving purposes.
boot - to start up a computer.
bug - a programming error that causes a program to behave in an unexpected way.
bus - an electronic pathway through which data is transmitted between components in a computer.
byte - a piece of computer information made up of eight bits.
card - a printed circuit board that adds some feature to a computer.
cartridge drive - a storage device, like a hard drive, in which the medium is a cartridge that can be removed.
CD-ROM - an acronym for Compact Disc Read-Only Memory.
Chooser - A desk accessory used to select a printer, or other external device, or to log onto a network.
Clipboard - A portion of memory where the Mac temporarily stores information. Called a Copy Buffer in many PC applications because it is used to hold information which is to be moved, as in word processing where text is "cut" and then "pasted".
Clock Rate (MHz) - The instruction processing speed of a computer measured in millions of cycles per second (i.e., 200 MHz).
command - the act of giving an instruction to your Mac either by menu choice or keystroke.
command (apple) key - a modifier key, the Command key used in conjunction with another keystroke to active some function on the Mac.
compiler - a program the converts programming code into a form that can be used by a computer.
compression - a technique that reduces the size of a saved file by elimination or encoding redundancies (i.e., JPEG, MPEG, LZW, etc.)
control key - seldom used modifier key on the Mac.
control panel - a program that allows you to change settings in a program or change the way a Mac looks and/or behaves.
CPU - the Central Processing Unit. The processing chip that is the "brains" of a computer.
crash - a system malfunction in which the computer stops working and has to be restarted.
cursor - The pointer, usually arrow or cross shaped, which is controlled by the mouse.
daisy chaining - the act of stringing devices together in a series (such as SCSI).
database - an electronic list of information that can be sorted and/or searched.
data - (the plural of datum) information processed by a computer.
defragment - (also - optimize) to concatenate fragments of data into contiguous blocks in memory or on a hard drive.
desktop - 1. the finder. 2. the shaded or colored backdrop of the screen.
desktop file - an invisible file in which the Finder stores a database of information about files and icons.
dialog box - an on-screen message box that appears when the Mac requires additional information before completing a command.
digitize - to convert linear, or analog, data into digital data which can be used by the computer.
disk - a spinning platter made of magnetic or optically etched material on which data can be stored.
disk drive - the machinery that writes the data from a disk and/or writes data to a disk.
disk window - the window that displays the contents or directory of a disk.
document - a file you create, as opposed to the application which created it.
DOS - acronym for Disk Operating System - used in IBM PCs.
DPI - acronym for Dots Per Inch - a gauge of visual clarity on the printed page or on the computer screen.
download - to transfer data from one computer to another. (If you are on the receiving end, you are downloading. If you are on the sending end, you are uploading ).
drag - to move the mouse while its button is being depressed.
drag and drop - a feature on the Mac which allows one to drag the icon for a document on top of the icon for an application, thereby launching the application and opening the document.
driver - a file on a computer which tells it how to communicate with an add-on piece of equipment (like a printer).
Ethernet - a protocol for fast communication and file transfer across a network.
expansion slot - a connector inside the computer which allows one to plug in a printed circuit board that provides new or enhanced features.
extension - a startup program that runs when you start the Mac and then enhances its function.
fibre channel - as applied to data storage and network topology - link to FC Glossary.
file - the generic word for an application, document, control panel or other computer data.
finder - The cornerstone or home-base application in the Mac environment. The finder regulates the file management functions of the Mac (copying, renaming, deleting...)
floppy - a 3.5 inch square rigid disk which holds data. (so named for the earlier 5.25 and 8 inch disks that were flexible).
folder - an electronic subdirectory which contains files.
font - a typeface that contains the characters of an alphabet or some other letterforms.
footprint - The surface area of a desk or table which is occupied by a piece of equipment.
fragmentation - The breaking up of a file into many separate locations in memory or on a disk.
freeze - a system error which causes the cursor to lock in place.
get info - a Finder File menu command that presents an information window for a selected file icon.
gig - a gigabyte = 1024 megabytes.
hard drive - a large capacity storage device made of multiple disks housed in a rigid case.
head crash - a hard disk crash caused by the heads coming in contact with the spinning disk(s).
high density disk - a 1.4 MB floppy disk.
highlight - to select by clicking once on an icon or by highlighting text in a document.
icon - a graphic symbol for an application, file or folder.
initialize - to format a disk for use in the computer; creates a new directory and arranges the tracks for the recording of data.
insertion point - in word processing, the short flashing marker which indicates where your next typing will begin.
installer - software used to install a program on your hard drive.
interrupt button - a tool used by programmers to enter the debugging mode. The button is usually next to the reset button.
K - short for kilobyte.
keyboard shortcut - a combination of keystrokes that performs some function otherwise found in a pulldown menu.
kilobyte - 1024 bytes.
landscape - in printing from a computer, to print sideways on the page.
launch - start an application.
Measurements (summary) -
*a bit = one binary digit (1 or 0) *"bit" is derived from the contraction b'it (binary digit) -> 8 bits = one byte
*1024 bytes = one kilobyte
*K = kilobyte
*Kb = kilobit
*MB = megabyte
*Mb = megabit
*MB/s = megabytes per second
*Mb/s = megabits per second
*bps = bits per second
i.e., 155 Mb/s = 19.38 MB/s
MB - short for megabyte.
megabyte - 1024 kilobytes.
memory - the temporary holding area where data is stored while it is being used or changed; the amount of RAM a computer has installed.
menu - a list of program commands listed by topic.
menu bar - the horizontal bar across the top of the Mac¹s screen that lists the menus.
multi finder - a component of System 6 that allows the Mac to multi task.
multi tasking - running more than one application in memory at the same time.
nanosecond - one billionth of a second. ( or, the time between the theatrical release of a Dudley Moore film and the moment it begins to play on airplanes).
native mode - using the computers original operating system; most commonly used when talking about the PowerPC can run software written for either the 80x0 systems, or the PowerPC¹s RISC code.
NuBus - expansion slots on the Mac which accept intelligent, self-configuring boards. NuBus is a different bus achitecture than the newer PCI bus and the boards are not interchangable.
operating system - the system software that controls the computer.
optical disk - a high-capacity storage medium that is read by a laser light.
palette - a small floating window that contains tools used in a given application.
partition - a subdivision of a hard drives surface that is defined and used as a separate drive.
paste - to insert text, or other material, from the clipboard or copy buffer.
PC - acronym for personal computer, commonly used to refer to an IBM or IBM clone computer which uses DOS.
PCI - acronym for Peripheral Component Interchange - the newer, faster bus achitecture.
peripheral - an add-on component to your computer.
point - (1/72") 12 points = one pica in printing.
pop-up menu - any menu that does not appear at the top of the screen in the menu bar. (may pop up or down)
port - a connection socket, or jack on the Mac.
Power PC - a processing chip designed by Apple, IBM and Motorola (RISC based).
Power Mac - a family of Macs built around the PowerPC chip.
print spooler - a program that stores documents to be printed on the hard drive, thereby freeing the memory up and allowing other functions to be performed while printing goes on in the background.
QuickTime - the Apple system extension that gives one the ability to compress, edit and play animation, movies and sound on the Mac.
RAM - acronym for Random-Access Memory.
reset switch - a switch on the Mac that restarts the computer in the event of a crash or freeze.
resize box - the small square at the lower right corner of a window which, when dragged, resizes the window.
RISC - acronym for Reduced Instruction Set Computing; the smaller set of commands used by the PowerPC and Power Mac.
ROM - acronym for Read Only Memory; memory that can only be read from and not written to.
root directory - the main hard drive window.
save - to write a file onto a disk.
save as - (a File menu item) to save a previously saved file in a new location and/or with a new name.
scroll - to shift the contents of a window to bring hidden items into view.
scroll bar - a bar at the bottom or right side of a window that contains the scroll box and allows scrolling.
scroll box - the box in a scroll bar that is used to navigate through a window.
SCSI - acronym for Small Computer System Interface.
SCSI address - a number between zero and seven that must be unique to each device in a SCSI chain. Fast and Wide SCSI devices will allow up to 15 SCSI Ids (hexidecimal); however, the length restriction (3 meters) is such that it is virtually impossible to link 15 devices together.
SCSI port - a 25 pin connector on the back of a Mac (native SCSI port); used to connect SCSI devices to the CPU. Some SCSI cards (like the ATTO) have a 68 pin connector.
SCSI terminator - a device placed at the end of a SCSI chain to complete the circuit. (some SCSI devices are self-terminating, or have active termination and do not require this plug).
serial port - a port that allows data to be transmitted in a series (one after the other), such as the printer and modem ports on a Mac.
server - a central computer dedicated to sending and receiving data from other computers (on a network).
shut down - the command from the Special menu that shuts down the Mac safely.
software - files on disk that contain instructions for a computer.
spreadsheet - a program designed to look like an electronic ledger.
start up disk - the disk containing system software and is designated to be used to start the computer.
surge suppressor - a power strip that has circuits designed to reduce the effects of surge in electrical power. (not the same as a UPS)
System file - a file in the System folder that allows your Mac to start and run.
System folder - an all-important folder that contains at least the System file and the Finder.
32 bit addressing - a feature that allows the Mac to recognize and use more than 8MB of memory.
title bar - the horizontal bar at the top of a window which has the name of the file or folder it represents.
upload - to send a file from one computer to another through a network.
Uninterruptible Power Source (UPS)- a constantly charging battery pack which powers the computer. A UPS should have enough charge to power your computer for several minutes in the event of a total power failure, giving you time to save your work and safely shut down.
UPS - acronym for Uninterruptible Power Source.
vaporware - "software" advertised, and sometimes sold, that does not yet exist in a releasable for.
virtual memory - using part of your hard drive as though it were "RAM".
WORM - acronym for Write Once-Read Many; an optical disk that can only be written to once (like a CD-ROM).
zoom box - a small square in the upper right corner of a window which, when clicked, will expand the window to fill the whole screen.
Tuesday, November 19, 2013
Basic Computer Components |
Computers come in all different shapes and forms (examples: desktops, laptops), but the main components that make up a computer pretty much stay the same. Components can also be refereed to as; hardware or parts. Throughout this website I will explain the various components in a PC computer, and try my best to give you the information you need to better understand how your computer works. Some of this information is considered basic computer knowledge, but there is no better place to start with than with the basics. Knowing this valuable information can help you if you are going to buy, repair, maintain or even build your own computer.
Every computer Consists of the following basic components:
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