Answer:
The doctors could see if her cells are getting the molecules they need from food and air
Step-by-step explanation:
The doctors could see if her cells are getting the molecules they need from food and air. Doing so allows the doctors a general overview of how well her body's biological systems are performing since the basic necessities of the human system are food and oxygen. Therefore if the body is receiving both food and oxygen properly and distributing it properly and efficiently as well without any problems then the most likely outcome is that she is healthy enough to perform her tasks in the submarine under more pressure.