Answer:
6.67 kg
Explanation:
The mass of the rock can be found by using the formula
[tex]m = \frac{f}{a} \\ [/tex]
f is the force
a is the acceleration
From the question we have
[tex]m = \frac{500}{75} = \frac{20}{3} \\ = 6.66666...[/tex]
We have the final answer as
6.67 kg
Hope this helps you
