11) Assume a liter of milk has an activity of 2400 pCi due to 40K. If a person drinks 2 glasses (0.460 l) per day, estimate the total dose (rem) received in a year. As a crude model, assume the milk stays in the stomach 13.5hr and is then released. Assume also that 15.0 percent of the 1.50 MeV released per decay is absorbed by the body. Calculate the dose in mrem. Make your calculation assuming this person is a 68.8 kg adult.

A net external force acts on a particle. This net force is not zero. Is this sufficient information to conclude that (a) the velocity of the particle change, (b) the kinetic energy of the particle changesm and (c) the speed of the particle changes? Give your reasoning in each case