What is the quaternary period?
A) the period when Earth began.
B) the last geologic era.
C) the first geologic era.
D) the present geologic era.
Question 2
Which of the following is not a way to add carbon dioxide to the atmosphere?
A) burning fossil fuels.
B) cooling of the oceans.
C) warming of the oceans.
D) land clearing for agriculture.
