1. Patients with Graves disease have an overactive thyroid gland. A common treatment uses radioactive iodine, which is taken up by the thyroid. The radiation emitted in its decay will damage the tissues of the gland. A single pill is produced with 4 x 10"* atoms of the isotope I- 131, which has a half life of 8 days. (a) How many atoms remain 24 hours after the pill's creation, when the pill is delivered to a hospital? (b) Although the iodine in the pill is constantly decaying, it is still useable as long as it contains at least 1.1 x 10"* I-131 atoms. What is the maximum delay before the pill is no longer usable? 2. Two radioactive isotopes, K-40 (half life = 1.3 x 10 yrs) and C-14 (half life = 5.7 x 10* yrs), are found in measureable quantities in your body. Suppose you have 1 mole of each. Which is more radioactive - that is, which has a greater activity