<span>A mirror neuron is a neuron that fires both when an animal acts and when the animal observes the same action performed by another. Thus, the neuron "mirrors" the behavior of the other, as though the observer were itself acting. Such neurons have been directly observed in primate species.</span>
<span>I believe the answer is this:
A free-diving vessel used to explore the ocean at great depths.
Hope this helps.</span>
A,C, D.. Those are correct ..
Enters the left atrium...this is the oxygenated blood from the lungs (pulmonary)
