A plate sliding into a subduction zone can trigger ____. a. ...

[K@]

A plate sliding into a subduction zone can trigger ____.
 
  a. midocean rise
  b. cratering
 c. volcanism
 d. hurricanes
 e. erosion

Question 2

If hydrogen (H2) gas is the most common molecule found within the interstellar medium, then why do astronomers measure the amount of carbon monoxide (CO) gas to map molecular clouds?
 
  What will be an ideal response?

[guyanai]

Answer to Question 1

c

Answer to Question 2

Hydrogen (H2) is the most common molecule in the Universe, but it does not radiate strongly in the radio part of the electromagnetic spectrum. Conversely, carbon monoxide (C) is a much less common molecule in the Universe, but it is a very efficient radiator of radio energy. Radio astronomers measure the amount of CO and use it to infer H2 concentrations to help map a molecular cloud.