Answer:
The answer is B) 0.57.
Step-by-step explanation:
In this problem we have to apply queueing theory.
It is a single server queueing problem.
The arrival rate is
and the service rate is
.
The proportion of time that the server is busy is now as the "server utilization"and can be calculated as:

where c is the number of server (in this case, one server).
Unfortunately, there's no diagram here! But the prism is described as "rectangular." Thus, the volume is simply (length)(width)(height) cubic inches. Multiply: (8 inches)(9 inches)(12 inches).