Writing exponential functions from scenarios a patient is given a 50 mg dose of medicine. the medicine's effectiveness decreases every hour at a constant rate of 40%. what is the exponential decay function that models this scenario? how much medicine will be left in the patient's system after 2 hours?
a. f(x) = 50(0.40)x; 8 mg
b. f(x) = 50(0.60)x; 18 mg
c. f(x) = 50(40)x; 80,000 mg
d. f(x) = 50(60)x; 180,000 mg