Stay patient and motivated, avoid browsing irrelevant things on the internet when you need to get something done, and take breaks and ask help when you need it... this is what I do so I hope this helps!
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 ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.
