Permafrost occurs in the tundra. what is permafrost?

If we represent the solar system on a scale that allows us to walk from the sun to pluto in a few minutes, then a) the planets are microscopic and the stars are millions of miles away. b) the planets are the size of basketballs and the nearest stars are a few miles away. c) the planets are marble size or smaller and the nearest stars are thousands of miles away.

What would have happened to portugal’s trade if they had not found a way to sail around the tip of africa

In what three areas is the us leader?