Solution:
(i)
$$\begin{tabular}{|l|l|}
\hline Class Interval & Frequency \\
\hline $0-10$ & 12 \\
\hline 10-20 & 20 \\
\hline 20-30 & 26 \\
\hline $30-40$ & 18 \\
\hline 40-50 & 10 \\
\hline 50-60 & 06 \\
\hline
\end{tabular}$$
Steps of construction:
(a) Mark the class intervals on $\mathrm{x}$-axis and the frequencies on $\mathrm{y}$-axis, by taking suitable scales.
(b) Construct rectangles with class intervals as bases and corresponding frequencies as heights.
(ii)
$$\begin{tabular}{|l|l|}
\hline Class Interval & Frequency \\
\hline 10-16 & 15 \\
\hline 16-22 & 23 \\
\hline 22-28 & 30 \\
\hline 28-34 & 30 \\
\hline 34-40 & 20 \\
\hline
\end{tabular}$$
Steps of construction:
(a) Mark the class intervals on $x$-axis and frequency on $y$-axis, by taking suitable scales.
(b) Construct rectangles with class intervals as bases and corresponding frequencies as heights.