Is 7- -5 equals negative 2?

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.

Advantages and disadvantages of mitigation and adaptation

How can studying economics us make better choices about how to use scare resources