Answer:
The gravitational potential energy of the 8.6 kg mass is 5.38x10⁸ J.
Step-by-step explanation:
We can find the gravitational potential energy of the mass using the following equation:

Where:
m: is the mass = 8.6 kg
g: is the gravity = 9.81 m/s^{2}
h: is the height = Earth's radius = 6371 km
Hence, we have:

Therefore, the gravitational potential energy of the 8.6 kg mass is 5.38x10⁸ J.
I hope it helps you!