12 3 4 5 6 7 8 9 10 the of exercise determines the health and fitness benefit of the exercise.
a. frequency
b. intensity
c. time
d. type

the aorta is the large artery leaving the heart branches into smaller arteries, which eventually branch into capillaries.the arteries carry oxygen and nutrients away from your heart, to your body's tissues. the capillaries are small, thin blood vessels that connect the arteries and the veins. the statement that arteries carry oxygen-rich blood to capillaries is true. veins on the other hand are blood vessels that take oxygen-poor blood back to the heart.

it contracts and pulls the lungs downwards. this opens the lungs and chest cavity and allows air to come into the lungs.