Base your answers on the graph below, which represents uniform cooling of a sample of a pure substance, starting as a gas. The boiling point of the substance is

120

Explanation:

Because it starts as gas at from A to B, B to C is gas and liquid equilibrium, so in order to go to boiling point (point where it goes from liquid to gas) it happens at 120 because after that you see that steep slope which represents the gas being formed.

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.