Which statement best describes an atom? protons and neutrons grouped in a specific pattern protons and electrons spread around randomly a ball of electrons and neutrons surrounded by protons a group of protons and neutrons that are surrounded by electrons

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.