The purpose of a battery in a circuit is to . provide a conductive path
increase the potential of charges in the circuit
decrease the potential of charges in the circuit
add charges to the circuit

Anyone know? will mark brainliest if correct!

Adoctor administers a drug to a 38-kg patient, using a dosage formula of 50 mg/kg/day. assume that the drug is available in a 100 mg per 5 ml suspension or in 500 mg tablets. a. how many tablets should a 38-kg patient take every four hours? b. the suspension with a drop factor of 10 ggt/ml delivers the drug intravenously to the patient over a twelve-hour period. what flow rate should be used in units of ggt/hr? a. the patient should take nothing pills every four hours. (type an integer or decimal rounded to the nearest hundredth as needed.)

Plz hurry evaluate the expression a+b where a=8 and b=19