For the reaction, `A rarr` Products, `-(d[A])/(dt)=k` and at different time interval, [A] values are
`{:("Time",0,"5 min","10 min","15 min"),([A],20M,18M,16M,14M):}`
At 20 min, rate of reaction in M m `"in"^(-1)` will be

Explanation

To solve the problem, we need to determine the rate of reaction at 20 minutes for the reaction \( A \rightarrow \text{Products} \). We are given the concentration of \( A \) at different time intervals, and we can use this information to calculate the rate of reaction.

### Step-by-Step Solution:

1. **Identify the Concentration Values**:
From the data provided:
- At \( t = 0 \) min, \([A] = 20 \, \text{M}\)
- At \( t = 5 \) min, \([A] = 18 \, \text{M}\)
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