Author Question: Which of the following human activities contributed to the pollution of our ancestral air? A) ... (Read 79 times)

kamilo84 · **on:** Aug 27, 2018

Which of the following human activities contributed to the pollution of our ancestral air?

A) Discovering, making, and using tools contributed to air pollution.
B) The discovery and use of fire contributed to air pollution.
C) The development of crop farming contributed to air pollution.
D) All of these contributed to air pollution.

Question 2

Petroleum jelly is

A) a mixture of low carbon number hydrocarbons.
B) a mixture of moderate carbon number hydrocarbons.
C) a mixture of higher carbon number hydrocarbons.
D) none of the above