Answer:
The answer is 90 kg
Explanation:
In order to find the mass of the football we use the formula
[tex]m = \frac{p}{v} \\ [/tex]
where
p is the momentum
v is the velocity
We have
[tex]m = \frac{630}{7} \\ [/tex]
We have the final answer as
90 kg
Hope this helps you
