Why do models suggest that Uranus and Neptune formed elsewhere? ...

[Medesa]

Why do models suggest that Uranus and Neptune formed elsewhere?
 
  A) We do not have very good models.
  B) The density of materials was too low in their current orbits for the ice giants to have formed there.
  C) Jupiter and Saturn took up most of the material in the area; Uranus and Neptune must have formed elsewhere.
  D) It is too cold at their current locations for the ice giants to have formed there.

Question 2

How can astronomers determine the mass of the Sun?
 
  What will be an ideal response?

[Perkypinki]

Answer to Question 1

B

Answer to Question 2

Using Newton's Laws, we know that gravity keeps the Earth in orbit around the Sun. Since the Earth's path is nearly circular, we can determine the size of the force keeping it on this path. Combining this equation (for centripetal force) with the gravity equation allows astronomers to calculate the Sun's mass.

[Medesa]

Wow, this really help

[steff9894]

Thanks for the timely response, appreciate it