$1.$ Design a direct mapping and $2$ way set associative mapping structure with $128$KB cache and $128$ MB memory size. Write the address limits of main memory, line numbers of cache, set numbers and number of bits. Explain the structure and write the advantages, drawback of the method.

$2.$ Explain one $1$ error correction process and solve the following problem. Assume that the $8-$bit input word is written to memory as $01010011,$ with data bit D$1$ in the rightmost position. A soft error occurs and D$4$ changes its state. Find the syndrome word and explain the process correcting D$4.$

$3.$ Explain how magnetic disks work coverin tracks, sectors$,$ multiple zone recording

$4.$ Explain the function of I$/$O module and the functions of its components

$5.$ Explain RAID and types of RAID