Pls help me I beg you

D. Nathan applies enough force through pushes to move the piano

Explanation:

What moves the piano is a net force that is applied through the effort of Nathan on the instrument.

Force is a pull or push on a body.

When force is applied on a body, it causes the state of motion of the body to change.

Therefore, if a body has a net force greater than zero, the body will in likewise begin to move. As Nathan pushes on the piano, it will eventually move.

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.