A first order reaction in `75%` complete is 60 minutes. Find the half life of this reaction.

Explanation

To solve the problem of finding the half-life of a first-order reaction that is 75% complete in 60 minutes, we can follow these steps:

### Step 1: Understand the reaction completion
Given that the reaction is 75% complete, it means that 75% of the initial concentration (A) has reacted. Therefore, the remaining concentration after 60 minutes is:

\[ \text{Remaining concentration} = A - 0.75A = 0.25A \]
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