Question

which of the following are human activities increase atmospheric greenhouse gas concentrations?
combustion of fossil fuels
emissions from landfills and wastewater treatment
agriculture and livestock production
deforestation
all of the above
question 13
1 pts
over the past thousand years, average global temperatures have varied by less than:
one degree
10 degrees
15 degrees
half a degree
five degrees

Explanation:

Combustion of fossil fuels releases carbon - dioxide. Landfills and wastewater treatment emit methane. Agriculture and livestock produce methane and nitrous oxide. Deforestation reduces the number of trees that absorb carbon - dioxide. Over the past thousand years, average global temperatures have varied by less than one degree.

Answer:

First question: E. All of the above
Second question: A. One degree