The mass of proton is 1.67×10kg and the mass of an electric is 9.11×10kg, calculate the force of gravitation between: (I) a proton and an electron (ii) two proton [g=6.67×10Nm kg, distance between the protons =4.0m, distance between the electrons =2× 10m, distance between the protons and the electron = 5.4 ×10m