A solid uniform sphere has a mass of 1.0 x 104 kg and a radius of 1.0 m. What is the magnitude of the gravitational force due to the sphere on a particle of mass m located at a distance of?

(a) 1.5 m and

(b) 0.50 m from the center of the sphere?

(c) Write a general expression for the magnitude of the gravitational force on the particle at a distance r < 1.0 m from the center of the sphere.