324 grams of water starting at 4.0°C is heated until its temperature is 37°C. Calculate the amount of heat energy needed to cause this rise in temperature. pls help me !!!​

Determine the empirical formula of a compound containing 40.6 grams of carbon, 5.1 grams of hydrogen, and 54.2 grams of oxygen. in an experiment, the molar mass of the compound was determined to be 118.084 g/mol. what is the molecular formula of the compound? for both questions, show your work or explain how you determined the formulas by giving specific values used in calculations.

Athe top of a hill, an athlete on a skateboard has x joules of mechanical energy. how much mechanical energy will she have at the bottom of the hill? ignore the effects of friction.

Is it safe to take 450mg of diphenhydramine hydrochloride?