How many times has rifting occurred along eastern North America since 600 million years ago?

A) once in the Mesozoic
B) once near the start of the Paleozoic
C) twice, once in the Mesozoic and once near the start of the Paleozoic
D) four times

Which of the following are true about factors that influence weathering?

A) Chemical weathering occurs fastest in cold or dry climates.
B) Whether a slope faces toward or away from the sun is not an important factor influencing weathering.
C) Soil and other weathering products tend to accumulate more on gentle slopes than on steep slopes.
D) Time is not a critical factor in weathering because physical and chemical processes have not changed much through time.

Which statement best describes cogeneration? 

A)  Natural gas is used as a backup for renewable energy sources. 
B)  Both heat and electricity are produced using the same fuel source. 
C)  It involves instruments, such as heat pumps, that can generate heating and cooling. 
D)  It combines passive solar and active solar technologies.

By what means do humans remove nitrogen from the soil? 

A)  harvesting nitrogen-poor crops 
B)  leaching water-soluble nitrate ions from soil through irrigation 
C)  applying organic fertilizers to agricultural land 
D)  mining nitrogen-poor mineral deposits

In 2012,the Harper government weakened protection for Canada's environment by making legislative changes so that _______________________________ statements were no longer required for projects involving federal money.

How much pollution can the oceans tolerate?