Answer:
20 km
Step-by-step explanation:
Draw a free body diagram. Weightlessness means there's no normal force.
Sum of forces in the centripetal direction (-y):
∑F = ma
mg = m v² / r
g = v² / r
r = v² / g
r = (440 m/s)² / (9.8 m/s²)
r = 20,000 m
r = 20 km