In an experiment four quantities $\mathrm{a}, \mathrm{b}, \mathrm{c}$ and $\mathrm{d}$are measured with percentage error $1\%,2\%,3\%$ and $4\%$ respectively. Quantity $\mathrm{P}$ is calculated as follows $\mathrm{P}=\frac{{\mathrm{a}}^3{\mathrm{b}}^2}{\mathrm{cd}}\%$ error in $\mathrm{P}$ is :

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 $=0.1\mathrm{s}$.

$\begin{array}{|llccc|}\hline & \begin{array}{c}\text{ Length of the }\\ \text{ pendulum (cm)}\end{array}& \begin{array}{c}\text{ Number of }\\ \text{ oscillation (}n\text{) }\end{array}& \begin{array}{c}\text{ Total time }\\ \text{ for (}n\text{) }\\ \text{ oscillations }\end{array}& \begin{array}{c}\text{ Time }\\ \text{ period }\\ \text{ (s) }\end{array}\\ \text{ I }& 64.0& 8& 128.0& 16.0\\ \text{ II }& 64.0& 4& 64.0& 16.0\\ \text{ III }& 20.0& 4& 36.0& 9.0\\ \hline\end{array}$

If $E_1, E_{11}$ and $E_{111}$ are the percentage errors in $g$, i.e., $\left(\frac{\mathrm{\Delta }g}{\mathrm{g}}\times 100\right)$ for students $\mathrm{I}$, $\mathrm{II}$ and $\mathrm{III}$, respectively.