Why is it better for those maps to use their own grid, instead of latitude and longitude?

What is the "great pacific garbage patch"? (a) a large area of marine debris concentrated by rotating ocean currents (b) a large area around the pacific rim where debris collects from natural disasters such as tsunamis (c) an area in the pacific ocean where trash is intentionally dumped due to lack of landfill availability (d) a large trash dump located in hawaii

5. what is a red giant? can our sun become a red giant? why or why not?

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