Assuming it starts at rest, the roller coaster only has potential energy at the top of the hill, which is

When it reaches the bottom, its potential energy will have converted to kinetic energy,

where
is its velocity at that point. By the law of conservation of energy, assuming no loss of energy due to other sources (e.g. sound, heat), we have


You are correct earth science is studied to predict planetery changes
Mg + kx = QE , k = 2.4 x = 0.074-0.059 , Q = 6.6C m = given solve
It goes in the downward direction
This response suggests that she is most likely in the pre-operational stage of cognitive development. This answer based on the Piaget's 4 Stages of Cognitive Development. The preoperational stage is the second stage of Cognitive development where human's have not yet reach the logical thinking ability. However<span>, the human already can think of image and object.</span>