The mass and related weight on the respective objects on four different planets

The mass and related weight on the respective objects on four different planets is
4 kg, 40n, earth
6 kg, 24n, mars
2 kg, 50n, jupiter
4 kg, 36n, venus
a) based on the information given, explain why the gravitational force on earth is stronger than on venus.(3%)
b) explain the relationship between the weight and the gravitational force of the planet on the object.(2%)
c) predict what will happen if the mass of the four planets is the same(3%)