Use the Answer Code Below to Complete the Following Statements

Use the answer code below to complete the following statements.
a.stroke volume
b.end-diastolic volume
c.cardiac output
d.heart rate
e.end-systolic volume
f.sympathetic activity
g.stroke volume and heart rate
h.end-diastolic volume and end-systolic volume
i.end-diastolic volume and sympathetic activity
-The number of times the heart contracts each minute is the _____.