#### Answer

$r$=$\frac{5}{\sqrt \pi}$

#### Work Step by Step

Step 1: The formula to be used here is, $r$=$\sqrt\frac{A}{\pi}$
Step 2: According to the question, A= 25 square meters
Step 3: Substituting the value of A into the equation, $r$=$\sqrt\frac{25}{\pi}$
Step 4: $r$=$\frac{5}{\sqrt \pi}$