Computer Science Test 7 Nddc Scholarship

The quality of a printed document is defined by its resolution, which is measured in 'dpi' or Dots Per Inch. This value represents how many individual dots of ink or toner a printer can place within a linear inch. A higher dpi count results in a sharper, more detailed image with smoother transitions between colours and finer text. For standard office documents, 300 to 600 dpi is typical, while professional high-quality photo printing often requires 1200 dpi or higher to achieve a clear, grain-free finish.

For professional business distribution, a colour laser printer is generally preferred over an inkjet. Laser printers use a dry powder called toner which is fused to the paper using heat, resulting in crisp text and vibrant, smudge-proof graphics that do not bleed. They are also much faster and more cost-effective for high-volume printing compared to inkjet printers. While an inkjet can produce high-quality photos, the precision and durability of laser output make it the standard for professional brochures, reports, and marketing materials.

This statement is true. When a computer is first turned on, it performs a Power-On Self-Test (POST) to ensure that essential hardware components like the CPU, RAM, and storage controllers are functioning correctly. Once the hardware is verified, the BIOS/UEFI locates the 'bootloader' on the storage drive, which then begins the process of loading the operating system into the computer's memory. If the POST fails, the computer will usually beep or display an error message and stop the boot process to protect the system.

This statement is true. 'Dragging' is a common mouse gesture used in graphical user interfaces to move objects on the screen or to select a range of text or multiple files. To perform this action, the user positions the pointer over an item, presses and holds the left mouse button, moves the mouse to a new location, and then releases the button to 'drop' the item. It is a fundamental interaction for organizing files, resizing windows, and performing various editing tasks within an application.

The keyboard combination Alt + Ctrl + DEL is a fundamental 'interrupt' command in Windows. When a program freezes or stops responding to user input, pressing these three keys simultaneously triggers a system-level security screen. From this menu, users can access the 'Task Manager', which provides a list of all active applications. By selecting the unresponsive program and clicking 'End Task', the operating system forces the application to shut down, reclaiming system resources without needing to restart the entire computer. This is a critical troubleshooting step for managing system stability.