The mass of Venus is 81.5% that of the earth, and its radius is 94.9% that of the earth

The mass of Venus is 81.5% that of the earth, and its radius is 94.9% that of the earth.

(a) Compute the acceleration due to gravity on the surface of Venus from these data.
(b) If a rock weighs 75.0 N on earth, what would it weigh at the surface of Venus?