Based on the map above, which of the following continents are the most developed? note, the darker the shade of green, the more developed the region is.

Does the threat of global warming require international cooperation? why or why not?

Drastic boundary changes can occur for all of the following reasons except for a. a shift in the way a river flows b. the collapse of a government system c. a conflict between two neighboring groups d. one country's decision to sell land to another country select the best answer from the choices provide

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