Answer:
a) -3.66233E22 N
b) 3.66233E22 N
Step-by-step explanation:
Closest distance between Earth and Sun = 1.471E8 kilometers = r
Mass of Earth = 5.97E24 kilograms = m
Mass of the sun = 1.989E30 kilograms = M
a) Universal gravitational constant = 6.6738E-11 N(m/kg)2

Force exerted by the sun on the earth they are closest together is -3.66233E22 N
b) The magnitude of the force that the earth will exert on the sun will be same but the direction will be different represented by the change of the sign

Force exerted by the earth on the sun when they are closest together is 3.66233E22 N.