Students $I$, $II$ and $III$ perform an experiment for measuring the acceleration due to gravity $(g)$ using a simple pendulum.
They use different lengths of the pendulum and /or record time for different number of oscillations. The observations are shown in the table.
Least count for length $=0.1 \mathrm{~cm}$
Least count for time $=0.1 \mathrm{~s}$
| Student |
Length of the pendulum $(cm)$ |
Number of oscillations $(n)$ |
Total time for $(n)$ oscillations $(s)$ |
Time period $(s)$ |
| $I.$ |
$64.0$ |
$8$ |
$128.0$ |
$16.0$ |
| $II.$ |
$64.0$ |
$4$ |
$64.0$ |
$16.0$ |
| $III.$ |
$20.0$ |
$4$ |
$36.0$ |
$9.0$ |
If $\mathrm{E}_{\mathrm{I}}, \mathrm{E}_{\text {II }}$ and $\mathrm{E}_{\text {III }}$ are the percentage errors in g, i.e., $\left(\frac{\Delta \mathrm{g}}{\mathrm{g}} \times 100\right)$ for students $\mathrm{I}, \mathrm{II}$ and III, respectively,