Maximum mass that the scale can rea is given as $M=50 \mathrm{~kg}$

Maximum displacement of the spring = Length of the scale, $I=20

\mathrm{~cm}$ $=0.2 \mathrm{~m}$

Time period is given as $T=0.6 \mathrm{~s}$

Maximum force exerted on the spring can be represented as

$\mathrm{F}=\mathrm{mg}$

where,

$\begin{array}{l}
\mathrm{g}=\text { acceleration due to gravity }=9.8 \mathrm{~m} / \mathrm{s}^{2} \\
\mathrm{~F}=50 \times 9.8=490
\end{array}$

So,

Spring constant can be calculated as $\mathrm{k}=\mathrm{F} / \mathrm{l}$

$=490 / 0.2$

We get,

$=2450 \mathrm{~N} \mathrm{~m}^{-1}$

Mass $\mathrm{m}$ is suspended from the balance.

Time period will be $\mathrm{t}=2 \pi \sqrt{\mathrm{m}} / \mathrm{k}$

So,

$\begin{array}{l}
\mathrm{m}=(\mathrm{T} / 2 \pi)^{2} \mathrm{x} \mathrm{k} \\
=\{0.6 /(2 \times 3.14)\}^{2} \times 2450
\end{array}$

We get,

$=22.36 \mathrm{~kg}$

Hence, weight of the body will be $=m g=22.36 \times 9.8$

$=219.13 \mathrm{~N}$

As a result, the weight of the body is about $219 \mathrm{~N}$