Suppose you are investigating how the day ends hamsters affect how much they run on the hamster wheel. in order to control the experiment which of these should you do? a. change only the diet of each hampster. b. give all the hamsters the exact same diet. c. only allow some hampsters to run on the wheel. d. compare the behavior of hamsters and gerbils

The space between two 15-in.-long concentric cylinders is filled with glycerin (viscosity = 8.5 × 10-3 lb·s/ft2). the inner cylinder has a radius of 1 in. and the gap width between cylinders is 0.1 in. determine (a) the torque and (b) the power required to rotate the inner cylinder at 180 rev/min. the outer cylinder is fixed. assume the velocity distribution in the gap to be linear.