There are 12 tasks: an input task, 10 computation tasks, and an output task. Each of the 12 tasks can be accomplished in 1 unit of time on one processor. The input task must complete before any computational tasks begin. Likewise, all 10 computational tasks must complete before the output task begins. The input task consumes the entire bandwidth of the input device. The output task consumes the entire bandwidth of the output device.

(a) What is the maximum speedup that can be achieved if this problem is solved on two processors? (Hint: Processors do not have to receive the message elements in order.)
(b) What is an upper bound on the speedup that can be achieved if this problem is solved with parallel processors?
(c) What is the smallest number of processors sufficient to achieve the speedup given in part (b)?
(d) What is the maximum speedup that can be achieved solving five instances of this problem on two processors? Continue to assume that there is one input device and one output device.
(e) What is an upper bound on the speedup that can be achieved solving 100 instances of this problem with parallel processors? Continue to assume that there is one input device and one output device.
(f) What is the smallest number of processors sufficient to achieve the speedup given in part (e)?