Averaged over a few heartbeats, venous return is cardiac output.
tra
O equal to
much higher than
O
much lower than
o
somewhat higher than
o
somewhat lower than
е
DELL

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.

c is the answer. hope this

the answer is