The formula for determining the gravitational potential energy of the balloon is expressed as
Energy = mgh
where
m is the mass of the ballon
g is the accelaration due to gravity and the value is 9.8m/s^2
h is the height of the balloon above the ground
From the information given,
m = 371
h = 615
Thus,
= 371 x 89.8 x615 = 22316017 NKJoulesJoules8298.651