How can we explain the presence of extrasolar planetary systems ...

[panfilo]

How can we explain the presence of extrasolar planetary systems with Jovian-sized planets at distances at which we normally find terrestrial planets?
 
  A) they are brown dwarfs that were captured by their parent stars
  B) these are massive terrestrial planets that formed close to their parent stars
  C) they are Jovian planets that were spun out from their rapidly spinning parent stars
  D) the Jovian planets formed farther out and then migrated inward

Question 2

What is the K-T boundary?
 
  A) a layer of dark sediment in the geological record formed at the same time humans learned to use fire
  B) a boundary between rocks containing the oldest life and older rocks that contained no life
  C) a boundary between the Earth's crust and the molten rock beneath it
  D) a layer of dark sediment in the geological record separating the Cretaceous and Tertiary periods of Earth's history

[Madisongo23]

Answer to Question 1

D

Answer to Question 2

D

[panfilo]

Excellent

[nanny]

Gracias!