The potential energy is defined as Ep=m*g*h where m is the mass of the body, g=9.81 m/s² and h is the height of the body. In our case m=0.01 kg and h=1.5 m. So when we input the values into the equation:
Ep=0.01*9.81*1.5= 0.14715 J.
So the potential energy of a grape is Ep=0.14715 J.