Which of the following ions has a direct effect on ventricular muscle contraction?

Free nerve endings are derived from heavily myelinated primary afferent fibers

a. True b. False

The physician orders promethazine (Phenergan®) 25 mg IM for a patient with nausea. The promethazine bottle is labeled "50 mg per mL.". How much of this drug should be administered to the patient?

0.5 mL 1 mL 1.5 mL 2.5 mL