In this activity, draw and count atoms to understand how nitrogen and hydrogen react to make ammonia. Draw the reactants using the drawing tool. Keep in mind that one molecule of nitrogen has two bonded atoms, and one molecule of hydrogen has two bonded atoms.

Chemical equation - N2 + 3H2 = 2NH3
[the two at the end of the first two are placed below the letter, aswell as the three in the last one]

i believe the answer is c

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.

c should be the answer

bacterium is not correct