A simple pendulum experiment is conducted. Given t1 and t2 values for 20 oscillations at l=50 cm, calculate T and T2.

Step 1: Prepare the data for plotting.
The period $T$ for a simple pendulum is given by $T = \frac{\text{Mean } t}{20}$, where Mean $t$ is the average time for 20 oscillations. The length $l$ must be in meters. We will calculate $T$ and $T^2$ using the provided $t_1$ and $t_2$ values.

First, let's correct the Mean $t$ for $l=50$ cm.
For $l=50$ cm: $t_1 = 29.00$ s, $t_2 = 28.60$ s.
Mean $t = \frac{29.00