Answer:
m=30.581kg
If you use 10m/s/s for your value of g then the answer is 30kg)
Explanation:
Assuming this is happening on earth, acceleration due to gravity (g) is 9.81m/s/s.
Force of gravity is the acceleration due to gravity multiplied by its mass:
F=mg
300=(9.81)m
m=30.581kg
If you use 10m/s/s for your value of g then the answer is 30kg)