A stone takes 5.4 seconds to fall from the top of a cliff. The cliff is meters high.
143
53
286
573

143

Explanation:

Using one of the 3 fundamental equations in physics, y=vo*t+1/2gt^2, we can use this equation to find the total distance that was traveled.

Acceleration due to gravity is always 9.8m/s^2 and time is 5.4s, we also have no initial velocity.

Given this, we can plug in the known variables.

y=0t+1/2*9.8*5^2

simplify,

y=4.9*5.4^2

y=4.9*29.16

y=142.884m which we can round up to 143 meters

Final 143 meters

that would be b i just took the test : )

pe = weightxheight = 2000x1000=2,000,000joules