When scientists make a statement or claim about what will happen in the future based on a past experience or evidence, they are making a/an

Prediction

Explanation:

A prediction is a scientific statement or claim about something that will happen in the future, using prior knowledge and reasoning.

So, when scientists predict something to happen in the future, they are making a prediction.

idk

explanation:

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.