Which of the following statements is/are true

Options

A. Work done by kinetic friction on a rigid body may be positive
B. a uniform spehre rolls up in inclined plane without sliding. The friction force on it will be up the incline. (only contanct force and gravitational force is acting).
C. a uniform sphere rolls down an inclined plane without sliding. The friction force on it will be up the incli.e (only contact force and gravitational force is acting)
D. A uniform sphere is left from rest from the top of the rough inclined plane. It moves down the plane with slipping. The friciton force on it will be up the incline.

Answer

ABCD