In the treatment of prostate cancer, radioactive implants are often used. The implants are left in the patient and never removed. The amount of energy that is transmitted to the body from the implant is measured in rem units as is given by E = " Poe ktdt, where k is the decay constant for the radioactive material, a is the number of years since the implant, and Po is the initial rate at which energy is transmitted. Suppose that the treatment uses iodine-125, which has a half-life of 60.1 days. (a) Find the decay rate, k, of iodine-125 (b) How much energy (measured in rems) is transmitted in the first four months if the initial rate of transmission is 8 rems per year?