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Radioactive Decay. Iodine-131 has a decay rate of 9.6% per day. The rate of change of an amount N of iodine-131 is given by
where t is the number of days since decay begin.
a. Let
b. Suppose 500 g of iodine-131 is present at
c. After how many days will half of the 500 g of iodine-131 remain?
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