Answer:
Step-by-step explanation:
Let's do this in Python. We know that the formula for the centripetal force caused by whirling the mass is:

where v is the speed (1, 10, 20, 40) and r = 3 m is the rope length.
Then we can use for loop to try calculating the tension force of each speed
def maximum_speed(m):
for speed in [1, 10, 20, 40]:
tension_force = m*speed^2/3
if tension_force > 60:
return speed
return speed