Describe the role of the "multiplication factor" in nuclear fission. What must f be to get a chain reaction?

Estimate the repulsive electrostatic force between two deuterium nucleii separated by a distance of 3 fm.

Briefly explain the difference between activity (in Ci or Bq), dose (in rad or Gy) and effective dose (in rem or Sv).

Estimate the total energy deposited in a person's tissues by a whole body dose of 10 mrem of alpha particles.