An experiment requires minimum `beta`-activity produced at the rate of 346 `beta`-particles per minute. The `t_((1)/(2)) " of" ""_(42)^(99)No`, which is a `beta`-emitter, is 66.6 hours. Find the minimum amount of `""_(42)^(99)Mo` required to carry out the experiment in 6.909 hours.

Explanation

To solve the problem, we need to determine the minimum amount of molybdenum-99 (Mo-99) required to produce a certain rate of beta particles over a specified time period. Here’s a step-by-step solution:

### Step 1: Understand the relationship between activity, decay constant, and number of atoms
The activity (A) of a radioactive substance is given by the formula:
\[ A = k \cdot N \]
where:
- \( A \) is the activity (in particles per minute),
- \( k \) is the decay constant,
...