These questions apply to the graph below. Can anyone explain + write the equations for d to g please? Thank you!

A frictionless 350 kg roller coaster begins from rest at point A. Determine the following.

a. The total mechanical energy at point A.
b. How fast is the roller coaster going at the bottom of the first hill?
c. The roller coaster is moving at 42.43 m/s at the “star”, what is the height of the star?
d. How fast is the roller coaster going at point B?
e. How fast is the roller coaster going at point C?
f. Point C and D are at the same vertical height. If a friction powered braking system applies a force of 800 N from point C to D. How much energy is loss to heat from the friction between point C and D? (Hint: Find the work done by friction)
g. How much total energy does the roller coast now have at point D?
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