Answer: D) All of the above Explanation: A computer has two types of memory. 1. Non-volatile and 2. Volatile.   Volatile memory is computer memory that requires power to maintain the stored information. * It is a temporary memeory which cannot contain information permanently. Example :: RAM or Random Access Memory   Non-volatile memory is computer memory that can retain the stored information even when not powered. * It is a permanent memory in which data is stored in permanently. Examples :: Hard disc, ROM, Floppy discs, Magnetic tape,...

Answer: A) DPI Explanation: Dots per inch (DPI, or dpi) is a measure of spatial printing or video or image scanner dot density, in particular the number of individual dots that can be placed in a line within the span of 1 inch (2.54 cm).

Answer: C) 8 bit Explanation: Word length refers to the number of bits processed by a computer's CPU in one go. These days, typically 32 bits or 64 bits are used. Data bus size, instruction size, address size are usually multiples of the word size.

Answer: C) Ctrl + Z Explanation: For undo the action or last action [Ctrl + Z] is used.