$A$ comet orbits the Sun in a highly elliptical orbit. Does the comet have a constant $(a)$ linear speed,$(b)$ angular speed,$(c)$ angular momentum,$(d)$ kinetic energy,$(e)$ potential energy,$(f)$ total energy throughout its orbit? Neglect any mass loss of the comet when it comes very close to the Sun.

(C, F) No. The linear speed changes as the distance from the Sun changes.
$(b)$ No. The angular speed changes according to Kepler's second law.
$(c)$ Yes. Since the gravitational force is a central force,the torque acting on the comet is zero,so angular momentum is conserved.
$(d)$ No. Kinetic energy changes as the linear speed changes.
$(e)$ No. Potential energy depends on the distance from the Sun,which varies in an elliptical orbit.
$(f)$ Yes. The total mechanical energy of the comet remains constant in the gravitational field of the Sun.