PLEASE HELP I CAN NOT FAIL THIS TEST I REALLY NEED HELP ASAP Which of the body's systems directly tells the heart when to beat?
OA. the circulatory system
OB. the nervous system
OC. the respiratory system
OD. the digestive system

Omg imgonnafailnfiedkla use complete sentences to explain how the mass of hydrogen is conserved during cellular respiration.

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.

Which of the following would have less momentum than a 52 kg cheetah running at 10 m/s?