Polly is pushing a box across the floor with a force of 30 N. The force of gravity is –8 N, and the normal force is 8 N. Which value could describe the force of friction if Polly could not move the box? –30 N
–8 N
8 N
30 N

a: 45.9 meters

b: 4.29 seconds

step-by-step explanation:

a: h(t)=1/2(-9.8)(3)^2+0(3)+90

h(t)=-4.9(3)^2+90

h(t)=-44.1+90

h(t)=45.9 meters

b: 0=1/2(-9.8)(t^2)+0t+90

0=-4.9t^2+90

-90=-4.9t^2

18.37=t^2

t=4.29 seconds

in the second question, the numbers aren't exact, but they're a close approximation.

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explanation:

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