Answer:
The veins that carry oxygenated bloof back into the heart are the pulmonary arteries.
Explanation:
Oxygen-rich blood flows from the lungs back into the left atrium (LA), or the left upper chamber of the heart, through four pulmonary veins. Oxygen-rich blood then flows through the mitral valve (MV) into the left ventricle (LV), or the left lower chamber.
Answer:

Explanation:

if temperature is constant.

if we are comparing two gases,

Let chlorine be Gas 1 and ethane be Gas 2
Data:
M₁ = 70.91 g/mol
M₂ = 30.07 g/mol
Calculation

<span>0.002 moles is the answer </span>
DNA is one and Grow and Develop i think i could be wong let me know i can read up on it some more