Earth's layers formed as result of differentiation. during differentiation, different zones of elements form layers and today we know these layers are made up of different elements. certain elements sunk to the center while others collected near the surface. we might predict that the elements, like iron and nickel, formed the core. a) heavier b) least dense c) light weight d) first crystallized

A) more dense

Explanation:

Just the USATestPrep and got it correct!

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.

lipid

explanation: