${v^2} = \frac{{2gh}}{{1 - {{\left( {\frac{{{A_0}}}{A}} \right)}^2}}}$
$ = \frac{{2 \times 10 \times 2.475}}{{1 - {{\left( {0.1} \right)}^2}}} = 50{m^2}/{s^2}$
Reason : Viscosity opposes the motion of balloon. Choose any one of the following four responses:
