If Galaxy A is found to have a recessional velocity four times ...

[nramada]

If Galaxy A is found to have a recessional velocity four times greater than Galaxy B, what can you say about their relative distances from Earth?
 
  a. Galaxy A is four times closer than Galaxy B.
  b. Galaxy A is four times further away than Galaxy B.
  c. Galaxy A is twice as distant than Galaxy B.
  d. Galaxy A is twice as close than Galaxy B.

Question 2

Explain what keeps the nuclear reactions in a star under control; i.e., what would happen if too large an amount of energy is released in the center?
 
  What will be an ideal response?

[KKcool]

Answer to Question 1

b
RATIONALE: Make two equations, one for Galaxy A and one for Galaxy B. Then divide like terms in both equations to create one big equation to solve after eliminating similar terms.

Answer to Question 2

If the star makes slightly too much energy, the extra energy flowing out of the star would force its layers to expand slightly, lowering the central temperature and density and slowing the nuclear reactions until the star regained stability.

[nramada]

TY

[KKcool]

You're welcome