Refer to your Expeditions in Reading book for a complete version of this text. Read the sentences from “Solar Power for Public Buildings.”

So pollution levels will drop. Big cities will have less smog. There will be fewer health problems from breathing dirty air. Rivers and streams will also be less contaminated. Drinking water will be cleaner.

How does the author relate the ideas in the sentences?

by using time order

by comparing two things

with cause and effect

with facts and statistics