please show work for number two thank you 3 A 20kg cart is

please show work for number two thank you !

3. A 20-kg cart is pushed up the inclined plane shown by a force F to a height of 3 m. What is the potential energy of the cart when it reaches the top of the inclined plane? (A) 1500J (B) 630 J (C) 600J 3m (D) 3003 (E) 150 J

Solution

3) C
   Potential Energy = m x g x h = 20 x 10 x 3 = 600 J

4) D

  Mechanical energy remains conserved which is equal to sum of kinetic and potntial energy of ball