5. What is the average rotational latency of a hard drive rotating at 7,200 RPM or 120 revolutions second? (Give your answer in milliseconds) [2 marks] Average Latency Time = X- 2 rotation speed 1 min Changes rotation speed to revolution per second = 7200 rev/min x ( 60 sec ) x 120 rev/sec Average Latency Time = X 120rev / sec = 0.004167 sec = 4.167 ms