Answer:
= 1 5/16
[/tex] 1 \frac{5}{16}[/tex]
Step-by-step explanation:

Expand

Collect like terms and simplify

Cross Multiply

Divide both sides of the equation by 80

You literally need to apply the formula

where
is the mass and
is the speed
I don't quite understand your question. Mind to ask more clearly?
Answer:
60% less
Step-by-step explanation:
its simple really.