Answer:
If the height is in metres, the speed is 24.25m/s
Weight = (mass) x (acceleration of gravity) .
On Earth, acceleration of gravity is 9.8 m/s² (rounded) .
650 N = (mass) x (9.8 m/s²)
Divide each side by (9.8 m/s²): 650 N / 9.8 m/s² = mass
Mass = 66.3 kilograms (rounded)