In lab #11 you worked with gamma rays of energy 661.659 kev emitted by a radioactive source 137 cs, which has a half-life of 30.17 years. the container enclosing the sample claims an activity of 0.5 pci nobody currently in the department knowns when the samples were purchased, so let's assume the claimed activity was correct 20 years ago. a) find the current activity of the source. express your answer in bequerels b) if you were to hold the source in your hand for the entire 110 minutes of lab (instead of actually doing the lab) how much energy would your hand adsorb, assuming perfect absorption. assume that the activity of the source does not measurably change in the 110 minutes c) how does your result in part (b) compare to your exposure to a typical dental -ray of 1014 ev per kilogram of tissue exposed? assume, for simplicity, that the mass of your hand. wrist, and part of your forearm, that is exposed to the 137cs is 1 kg. aside from the academic and intellectual danger of foregoing the laboratory experience, is holding the 137cs source physically dangerous? explain