Question Discussion & Solution

The correct answer is ROM.

Key Points

• Each memory cell of a ROM chip has either a transistor for a 1 bit or none for a 0 bit.
• ROMs(Read-only memory) is used for programs that are essential parts of a computer’s operation, such as the bootstrap program that starts a computer and loads its operating system or the BIOS (basic input/output system) that addresses external devices in a personal computer (PC). 
• EPROM (erasable programmable ROM), EAROM (electrically alterable ROM), and flash memory are types of nonvolatile memories that are rewritable, though the rewriting is far more time-consuming than reading.
• They are thus used as special-purpose memories where writing is seldom necessary—if used for the BIOS, for example, they may be changed to correct errors or update features.

Additional Information

• Cache memory:
  • Cache memory, also called Cache, a supplementary memory system that temporarily stores frequently used instructions and data for quicker processing by the central processor of a computer.
  • The cache augments and is an extension of, a computer’s main memory.
  • Both main memory and cache are internal, random-access memories (RAMs) that use semiconductor-based transistor circuits.
  • The cache holds a copy of only the most frequently used information or program codes stored in the main memory; the smaller capacity of the cache reduces the time required to locate data within it and provide it to the computer for processing. 
• RAM:
  • RAM, in full random-access memory, Computer main memory in which specific contents can be accessed (read or written) directly by the CPU in a very short time regardless of the sequence (and hence location) in which they were recorded.
  • Two types of memory are possible with random-access circuits, static RAM (SRAM) and dynamic RAM (DRAM).
  • A single memory chip is made up of several million memory cells.
  • In an SRAM chip, each memory cell stores a binary digit (1 or 0) for as long as power is supplied.
  • In a DRAM chip, the charge on individual memory cells must be refreshed periodically in order to retain data.
  • Because it has fewer components, DRAM requires less chip area than SRAM; hence a DRAM chip can hold more memory, though its access time is slower.

The correct answer is Kernel.

Key Points

• The first program loaded on start-up and manages computer system resources is Kernel.
• A kernel is the central part of an operating system.
• It manages the operations of the computer and the hardware, most notably memory and CPU time.
• There are five types of kernels:
  • A microkernel, which only contains basic functionality
  • A monolithic kernel, which contains many device drivers
  • Hybrid Kernel
  • Exokernel
  • Microkernel

Additional Information

• Resources under the Operating System control:
  • The processor.
  • Main memory.
  • Input/Output Device.
  • Secondary storage devices.
  • Communication devices and ports. 

The correct answer is Cell address.

Key Points

• A cell reference or cell address is a combination of a column letter and a row number that identifies a cell on a worksheet.  
• For example, A1 refers to the cell at the intersection of column A and row 1, B2 refers to the second cell in column B, and so on.
• It is basically a cell's column number and row number.

Important Points

• In MS Excel, columns are defined with Alphabets like A, B, C....and so on.
• While rows are defined with numerical values like 1, 2, 3, 4,.......and so on.

Memory in a computer system is required for the storage and retrieval of the instructions and data. A system uses a variety of devices for storing the instructions and data that are required for its operation.

1. CPU registers - They are part of the control unit and ALU rather than the memory. Hence their contents can be handled much faster than any content of memory.

2. Cache Memory: It stores program instruction and data that the computer uses more frequently. The processor can access this information from the cache rather than having to get it from the computer’s main memory. Hence, it is faster than RAM.

3. Primary or main memories are used mainly for primary storage. It stores programs and data which are currently needed by the CPU. The primary memory is a static device. There is no rotating part in it. Examples include RAM, ROM, etc.

• Random Access Memory (RAM): It stores data that the computer needs to use temporarily. So it is faster than the secondary storage devices. It is a volatile memory i.e. the data disappear from it when the power is off. The amount of RAM in a computer system can affect a computer’s performance.
• Read-Only Memory (ROM): The system uses ROM to boot itself. It is used to store the start-up information of the computer. This is called non-volatile memory i.e. it retains its content even if the computer loses its power.

4. Secondary Memory: It is the storage that the CPU cannot access directly. Its content firstly needs to be copied into ram and then transferred to CPU. It stores data that can be easily retrieved only by the main memory and used by the processor. For example, hard disk.

Hence, the lists of computer memory types from lowest to highest speed are- 

Secondary Storage < Main Memory < Cache Memory

Therefore, Option 2 is the correct answer.

The correct answer is 1 megabyte.

Key Points

• Computer data storage conversions: