Step-by-step explanation:
a) Case1, by the formula, ke=½mv².
m=2kg, v=2m/s
ke = ½×2×2² = 4J
Case2, by the formula, ke=½mv².
m=4kg, v=3m/s
ke = ½×4×3² = 18J
therefore, the second object has more kinetic energy.
b) Case1, by the formula, pe = mgh
m=2kg, g=9.8m/s²(not given)(can consider 10m/s² when given), h= 10m
Pe1(write 1 in subscript) = 2×9.8×10= 196J.
Case2, by the formula, pe = mgh
m=4kg, g=9.8m/s²(not given)(can consider 10m/s² when given), h= 10m
Pe2(write 2 in subscript) = 4×9.8×10= 392J.
so, the object 2 has more potential energy.
hope this helps you.