Answer:
Blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. As the atrium contracts, blood flows from your right atrium into your right ventricle through the open tricuspid valve.
Explanation:
Animals, they only have a cell membrane, not cell walls.
I don't know what the answer choices were, though, but I hope this helps.
The first sentence is true
The answer is b because there are cracks in the ocean that are caused by two plates crashing
