9514 1404 393
Answer:
3.14^2 = 9.8596
Explanation:
The way this question is written, f(r) is a constant equal to 3.14^2 = 9.8596. It is the same constant value regardless of the value of r.
f(5) = 9.8596
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Additional comment
This looks suspiciously like the equation for the area of a circle:
A = πr^2 = 3.14r^2
For r = 5, this is ...
A = 3.14·5^2 = 3.14·25 = 15.7