Answer:
A) 15.0 years
Explanation:
Due to the distance to the star system is in light-year units, we can compute the time by using:

then, Rob will take to complete the trip about 15 light-years.
hope this helps!!
Answer:
b
Explanation:
The space shuttle, in circular orbit around the Earth, collides with a small asteroid which ends up in the shuttle's storage bay.
This form of collision is called inelastic collision. And inelastic collision momentum is conserved but the kinetic energy is not conserved. Hence the correct option is b. only momentum is conserved.
The total energy equation would be Kinetic energy+Potential energy