Answer :
Multiply 5 newton by each height. 1st is 5 joules, 2nd is 7.5, while 3rd is 10 joules.
Yo sup??
potential energy is given by
U=mgh
mg=5 N
U1=5*1=5 J
U2=5*1.5=7.5 J
U3=5*2=10 J
Hope this helps.