PLS help me im so close to be done

What does the term "deforestation" mean? what landform are we studying that deforestation is impacting greatly in brazil? describe how and why this is happening. plz me!

As our current atmosphere formed, the concentrations of various atmospheric gases fluctuated. match each gas with the explanation that best describes how its proportion changed during the evolution of the atmosphere.

Which best expresses the radical republican philosophy of reconstruction? a. the confederate states were conquered territories that should be ruled by military governors. b. the southern states actually never left the union. c. if ten percent of the voters of a state that had seceded took an oath of allegiance to the union, then it should be readmitted as a state.