( Would someone be able to help me with this question please and thank you). Need Help ASAP. I posted a picture of the question. There are three parts.

Explanation:
There are three parts
1. bob
The rock which is fixed to the string .
2.point of suspension(s)
The end of the string from where the stone is tied
3.Length of a pendulum(L)
The length between the center of gravity of the stone to the end of the string (point of suspension).