Question

1. what human activity can have the greatest positive change on global climate change by help to reduce the amount of carbon dioxide in the atmosphere?

a. building homes out of metal instead of wood
b. recycling plastics
c. limiting engines that use fossil fuels for energy
d. using alternatives to chlorofluorocarbons (cfcs) for refrigeration

1. the picture to the right shows the extent of summer arctic sea ice in 1979 and 2005. which hypothesis is best supported by the changes in sea - ice overage?

a. earth’s climate is gradually warming.
b. sea ice is migrating away from earth’s poles.
c. arctic sea ice is increasing in size.
d. global warming occurs only at earth’s poles during the summer.

1. how do scientists collect evidence about climate changes?

a. using remote sensing from space satellites
b. using ground - based measurements of temperatures and carbon dioxide, and sea level
c. by collecting information from tree rings, ice cores, and historical records
d. all of the above

Explanation:

Answer:

c. limiting engines that use fossil fuels for energy
a. Earth's climate is gradually warming.
d. all of the above