The relationship between the period T and the length T of a smile pendulum is T = 2\( \pi \) \( ( \frac{I}{g}) ^{ \frac{1}{2} } \). From experiment data of T and I, one can obtain the following graphs, i. T vs.I ii. T vs I² iii. T² vs. I iv. T vs \( \sqrt{I} \) v. logT vs logI. Which of the following graphs, are linear?

• A.all
• B.only i and ii
• C.only iii and iv
• D.iii,iv and v
• E.none of them