Why do more cancer deaths (as a percentage of population) occur in the U. S. than in poor regions of Africa or Asia?
Select one:
a. pollution is worse is the U. S.
b. the population is more mixed than in most nations
c. the population tends to be older in the U. S.
d. there is more radiation in the U. S. from bomb testing

D

Explanation:

There is more radiation in the US from bomb testing

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.

answer: accepted answer: aquatic animals use the oxygen dissolved in water to carry out respiration. since the amount of dissolved oxygen in water is low as compared to the amount of oxygen in the air, therefore the rate of breathing in aquatic animals is much faster than it is in terrestrial animals.

explanation: