Which of the following best describes convection? A) It is the ...

[Mr.Thesaxman]

Which of the following best describes convection?
 
  A) It is the process by which rocks sink in water.
  B) It is the process in which warm material expands and rises while cool material contracts and falls.
  C) It is the process in which warm material gets even warmer and cool material gets even cooler.
  D) It is the process in which a liquid separates according to density, such as oil and water separating in a jar.
  E) It is the process in which bubbles of gas move upward through a liquid of the same temperature.

Question 2

Like other solid bodies in the solar system, Earth's surface was kept molten by
 
  A) radioactivity.
  B) differentiation.
  C) convection.
  D) bombardment by small bodies.
  E) the solar nebula.

[zhanghao]

Answer to Question 1

B

Answer to Question 2

D

[Mr.Thesaxman]

TY

[zhanghao]

You're welcome