What effect contributed to the drastic conditions of the atacama desert

How many countries have portuguese as a national language?

According to the earth science reference tables, during which geologic time period were the continents of north america,south america, and africa closest together?

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.