Lag1989 problem number 5.1

Determine the mass M and the average density ρ of the Earth according to the following data: the average radius of the Earth R=6.37*10⁶m, the acceleration of free fall on the surface of the Earth g = 9.81 m / s²; gravitational constant G=6,67·10⁻¹¹ м³/(кг·с²);