A paratrooper jumps from an aeroplane and opens a parachute after 2 s of free fall and starts deaccelerating with 3 m / s^2. At 10 m height from…

A paratrooper jumps from an aeroplane and opens a parachute after $\displaystyle 2$ s of free fall and starts deaccelerating with $\displaystyle 3 \mathrm{~m} / \mathrm{s}^2$. At $\displaystyle 10$ m height from ground, while descending with the help of parachute, the speed of paratrooper is $\displaystyle 5 \mathrm{~m} / \mathrm{s}$. The initial height of the airplane is $\displaystyle \_\_\_\_$ m. ( $\displaystyle \mathrm{g}=10 \mathrm{~m} / \mathrm{s}^2$ )