$SD =2-\frac{1}{3}=\frac{5}{3}$
Area of $OABS$ is $A _{1}$
Area of $SCD$ is $A _{2}$
Distance $=\left| A _{1}\right|+\left| A _{2}\right|$
$A _{1}=\frac{1}{2}\left[\frac{13}{3}+1\right] 4=\frac{32}{3}$
$A _{2}=\frac{1}{2} \times \frac{5}{3} \times 2=\frac{5}{3}$
Distance $=\left|A_{1}\right|+\left|A_{2}\right|$
$=\frac{32}{3}+\frac{5}{3}$
$=\frac{37}{3}$
$[g = 10\,m/{s^2}]$