Consider a typical disk that rotates at $$15000$$ rotations per minute $$(RPM)$$ and has a transfer rate of $$50 \times {10^6}\,\,\,bytes/\sec .$$ If the average seek time of the disk is twice the average rotational delay and the controller’s transfer time is $$10$$ times the disk transfer time, the average time (in milliseconds) to read or write a $$512$$-byte sector of the disk is ______________________.

Consider a processor with byte-addressable memory. Assume that all registers, including Program Counter $$(PC)$$ and Program Status Word $$(PSW),$$ are of size $$2$$ bytes. A stack in the main memory is implemented from memory location $${\left( {0100} \right)_{16}}$$ and it grows upward. The stack pointer $$(SP)$$ points to the top element of the stack. The current value of $$SP$$ is $${\left( {016E} \right)_{16}}$$. The CALL instruction is of two words, the first word is the op-code and the second word is the starting address of the subroutine (one word $$= 2$$ bytes). The CALL instruction is implemented as follows:

$$ \bullet \,\,\,\,\,\,\,\,$$ Store the current value of $$PC$$ in the stack
$$ \bullet \,\,\,\,\,\,\,\,$$ Store the value of $$PSW$$ register in the stack
$$ \bullet \,\,\,\,\,\,\,\,$$ Load the starting address of the subroutine in $$PC$$

The content of $$PC$$ just before the fetch of a CALL instruction is $$\left( {5FA0} \right){\,_{16}}.$$ After execution of the CALL instruction, the value of the stack pointer is

Assume that for a certain processor, a read request takes $$50$$ nanoseconds on a cache miss and $$5$$ nanoseconds on a cache hit. Suppose while running a program, it was observed that $$80\% $$ of the processor's read requests result in a cache hit. The average read access time in nanoseconds is __________.

Which one of the following hash functions on integers will distribute keys most uniformly over $$10$$ buckets numbered $$0$$ to $$9$$ for $$𝑖$$ ranging from $$0$$ to $$2020$$?