One man is sitting on the shores of a river.

For near point of boat

$\mathrm{R}=5 \mathrm{~m}=\frac{\mathrm{u}^{\mathrm{m}} \sin 2 \theta}{\mathrm{g}} \mathrm{g}$

$5=\frac{(10)^{2} \sin 2 e}{g}$

$\theta=15^{\circ}$ or $75^{\circ}$

For for point of boat

$\mathrm{R}=6 \mathrm{~m}=\frac{\mathrm{u}^{\mathrm{a}^{\mathrm{s}} \sin 2 \theta}}{\mathrm{g}}$

$\theta=18^{\circ}$ or $71^{\circ}$

For a successful shot angle may vary from $15^{\circ}$ to $18^{\circ}$ or $71^{\circ}$ to $75^{\circ}$

Minimum angle $=15^{\circ}$

Maximum angle $=75^{\circ}$