In a thunderstorm, lightning strikes the ground 3 km away from you. The speed of sound on a terribly hot day is 0.388 km/s. How many seconds will elapse before you hear the sound? Round to the nearest tenth of a second.

Butane gas reacts with oxygen gas to give carbon dioxide gas and water vapor (gas). if you mix butane and oxygen in the correct stoichiometric ratio, and if the total pressure of the mixture is 390 mmhg, what is the pressure (in mmhg) of water vapor after the reaction is completed (temperature and volume do not change).