Why is photosynthesis a very important evolutionary and geological step in the history of life?

Given: circle a externally tangent to circle b. how many possible common tangents to circles a and b can exist? 2 3 4

Analyze the map below and answer the question that follows. image by mdf the map projection above was created using mathematical formulas to calculate distances. it has a small amount of distortion. which map projection is shown in this image? a. the goode projection b. the political projection c. the mercator projection d. the winkel tripel projectio

What are the answers for the following questions?