Can someone me with these questions ? : )

Which best describes red blood cells? a. they are colorless b. they protect against disease-carrying microorganisms c. they transport oxygen throughout the body d. they aid in blood clotting

During sunny hours, a large amount of build up between the hours of 1: 00-5: 00 pm. a. ozone b. mercury c. lead d. sulfuric acid

Imagine ? person stepping on a pin and pulling his or her foot way look at the réfléchir arc of the scenarios below