Which of the phrases from the passage best helps the reader understand the meaning of regulator?
A. Supply the exact amount of fuel needed for an engine to run.
B. The piece that fits into the divers mouth.
C. Automatically adjusted the pressure of the air in the tank.
D. The system was being sold in several countries throughout the world

What conclusion can be drawn about sea walls?

Read the passage: canines may not be the deepest thinkers in the world. but perhaps that's for the best. the life of a dog—sitting alone all day, waiting for everyone to come home—can be pretty boring. super-smart animals would probably get totally stressed out, says university of pennsylvania researcher james serpell. look at it this way: if dogs were any smarter, they probably wouldn't choose to hang around with us. which best describes the tone of the passage?

Yes or no? biology is the study of rocks and minerals.