1) Explain the difference between exposure to radioactivity from a source external to the body versus a source that has been consumed and is therefore inside the body.
2)Write the nuclear equations to represent each process:
a) alpha decay of Rn-220
b) beta decay of Bi-212
3) I-131 has a half life of 8.04 days. If a sample initially contains 20.0 grams of I-131, approximately how much I-131 will be left after 32 days?