The velocity of the spacecraft with respect to the Sun is

the velocity of the comet in the reference system of the spacecraft is

So, the velocity of the comet in the reference system of the Sun will be

And the negative sign tells us that the comet is directed toward the Sun.
Answer:
The net torque about the pivot is and the answer is 'c'
c. 
Explanation:

The torque is the force apply in a distance so it is the moment so depends on the way to be put it the signs so:





Now to find the net Torque is the summation of both torques


Magnetic field describea magnet's ability to act at a distance
Well, that would be a plane (flat) mirror
<span>provided that </span>
<span>the mirror and the object are oriented parallel to each other</span>