The Goodyear blimp, which frequently fly over sporting events, holds approximately 175,000 ft3 of helium. If the gas is at 23 oC and 1.0atm, what mass of helium is in the blimp?

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

Sulfuric acid (a component of acid rain) reacts with limestone (calcium carbonate) to produce calcium sulfate and carbon dioxide. this damages buildings and statues made of limestone. which solution of sulfuric acid will damage these structures more quickly? a. 0.001% b. 0.005% c. 0.010% d. 0.015%

What is the standard unit of measure for acceleration?