Answer:
1. a) warming
2. a) cooling
Step-by-step explanation:
1. Deforestation leads to more carbon dioxide and less oxygen in the atmosphere, because trees are in charge of taking in CO2 and releasing O2. More of the sun's radiation is reflected back to Earth if there's more CO2 in the atmosphere, which is why it has a warming effect on climate.
2. During a volcanic eruption, a volcano releases ash or dust particles that shade sunlight, which causes temporary cooling. The smallest particles can stay in the stratosphere for months, blocking sunlight, causing a long cooling effect on climate.