A data storage system consists of 3 disk drives sharing a common queue. An average of 53 storage requests arrive per second. The average time to service a request is 0.03 seconds. Assume that arrivals are poisson distributed and that service times are exponentially distributed. a. What is the probability that a given disk drive is busy?
b. What is the probability that no disk drives are busy?
c. What is the probability that a storage request will have to wait?
d. What is the average number of storage requests present in the system?

Afluid flows with a velocity field given by v=(x/t)i.. determine the local and convective accelerations when x=3 and t=1.

Burgers vector is generally parallel to the dislocation line. a)-true b)-false

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.