Science:Math Exam Resources/Courses/MATH110/December 2014/Question 09 (a)/Solution 1

Observe that the input of $A(r(t))$ is time $t$ (min) and the output is the area (square centimetres) of a ripple.

Therefore, $A(r(t))$ represents the area of the ripple, in square centimetres, at time ${\textstyle t}$ minutes.

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