A roller coaster has two hills and starts from rest atop the first hill , which is the higher of the two hills . The secound hill increases if the height of the initial hill is increased by 20m

Answer 1

Your question makes no sense to me.

Answer 2

The roller coaster can not make it to the top of the second hill if the first hill is not higher.
(1/2) m v^2 + m g h = constant