## Algebra and Trigonometry 10th Edition

$80~beats~per~second$
The pulse of the patient is the frequency of the given function. The frequency is the inverse of the period. According to item (b) the period is 0.75 seconds: $f=\frac{1}{0.75}=\frac{4}{3}~beats~per~second=\frac{4}{3}\times60=80~beats~per~second$