$$H_{0}=H-\frac{2}{3}D=31-\frac{2}{3}\times9=25[m]$$
$H_{0}=-\frac{2D}{3}+H\text{ and }-\frac{2D}{3}+H=25\text{ and }m=1$
$m=1$
$H_{0}=25\text{ and }H=\frac{2D}{3}+25$
$H_{0}=25$
$H=\frac{2D}{3}+25\text{ and }m=1$
