The correct option is D 32 N
At the surface of Earth, weight W=72N
∴F=mg=72N
m=7210=7.2kg
Now, at some height, h acceleration due to gravity is given as
g′=g(1+hR)2
Here, h=R2
g′=g(1+12)2=49g=4.44m/s2
Now, the force experienced by the body at half of the radius of the earth is given by:
F′=mg′=7.2×4.44=31.97N≈32N