Obtain the amount of `.^60Co` necessary to provide a radioactive source of `8.0 Ci` strength. The half-life of `.^60Co` is `5.3` years?

Explanation

To solve the problem of finding the amount of \( ^{60}Co \) necessary to provide a radioactive source of \( 8.0 \, \text{Ci} \) strength, we will follow these steps:

### Step 1: Understand the relationship between activity, number of nuclei, and decay constant

The activity \( R \) of a radioactive substance is given by the formula:
\[ R = n \lambda \]
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