Long description

Part (a): A vertical rectangular block labeled One program counter has four partitions, out of which the third partition is large. The partitions from top to bottom are labeled A, B, C, and D. Partition A is labeled Process switch. Four downward arrows point to each block individually, starting from one program counter to A, A to B, B to C, and C to D. Part (b): Four vertical rectangular blocks have arrows starting from a point labeled Four program counters. The four blocks are labeled A, B, C, and D and all blocks are marked with downward arrows. Part (c): Graph: The horizontal axis is labeled Time. The vertical axis is labeled Process. The range of processes is A, B, C, and D. Two sets of horizontal bars are marked at every process in the form of low to high step ladder.