George's highest target heart rate is 170. yesterday on the stair stepper machine, his heart rate went to 172. what should he do the next time he uses this machine to get the most effective workout?

use the settings of the machine to increase the intensity

use the settings of the machine to decrease the intensity

use a workout app to calculate a longer workout duration

use a workout app to calculate a shorter workout duration

Check all that occur during ventricular systole. a. the av valves open to allow blood to enter the ventricles from the atria. b. the av valves open to allow blood to enter the ventricles from the atria. c. the semilunar valves remain closed throughout systole to prevent backflow of blood into the ventricles. d. the semilunar valves remain closed throughout systole to prevent backflow of blood into the ventricles. e. the semilunar valves open to allow blood to flow into the large arteries. f. the semilunar valves open to allow blood to flow into the large arteries. g. the av valves close to prevent backflow of blood into the atria.