Givens.
• The mass of the ballon is 2.30 kg.
,
• The height is 35.65 m.
First, find the final velocity when the balloon is at the bottom. Use a formula that relates height, initial speed, final speed, and gravity.
![v^2_f=v^2_0+2gh](https://img.qammunity.org/2023/formulas/physics/college/v0l3c7upaf2ef7bkt3hz258o6wltnjttmu.png)
Where
• v_0 = 0 because the balloon starts from rest.
,
• Gravity is g = 9.8 m/s^2.
,
• h = 35.65 m.
Use all these magnitudes to find the final velocity v_f
![\begin{gathered} v^2_f=0^2+2(9.8\cdot(m)/(s^2))(35.65m) \\ v^2_f=698.74m^2 \\ v_f=\sqrt[]{698.74m^2} \\ v_f\approx26.4((m)/(s)) \end{gathered}](https://img.qammunity.org/2023/formulas/physics/college/9v4m09lt9byild412rhfewweclyzad587k.png)
Once we have the velocity at the bottom, find the kinetic energy using its formula.
![K=(1)/(2)mv^2](https://img.qammunity.org/2023/formulas/physics/college/89ts55elkus9wrqy6baloxb543n3yrist9.png)
Where m = 2.30 kg, and v = 26.4m.s.
![\begin{gathered} K=(1)/(2)\cdot(2.30\operatorname{kg})\cdot(26.4((m)/(s)))^2 \\ K=1.15\cdot696.96J \\ K=801.5J \end{gathered}]()
Therefore, the kinetic energy at the bottom is 801.5 J.