Let g be the acceleration due to gravity at the earth's surface and K the rotational kinetic energy of the earth. Suppose the earth's radius decreases by 2%. Keeping all other quantities constant, then
a. g increases by 2% and K increases by 2%
b. g increases by 4% and K increases by 4%
c. g decreases by 4% and K decreases by 2%
d. g decreases by 2% and K decreases by 4%