A hollow spherical shell with mass 1.95 kg rolls without slipping down a slope that makes an angle of 34.0 degrees with the horizontal.

a. Find the magnitude of the acceleration of the center of mass of the spherical shell.

b. Find the magnitude of the frictional force acting on the spherical shell.

c. Find the minimum coefficient of friction needed to prevent the spherical shell from slipping as it rolls down the slope.