Answer
$T^2=\frac{8a^3}{d^2}$
Work Step by Step
Step 1. Write the general form as $T^2=\frac{ka^3}{d^2}$ where $k$ is a constant.
Step 2. Use the given condition, $2^2=\frac{2^3k}{4^2}$, thus $k=8$
Step 3. We have $T^2=\frac{8a^3}{d^2}$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.