What are some characteristics of scientific questions ?

Apatient is in need of hydration. which type of solution are the patient's cells most likely in?

Compare the composition of the moon's surface with the composition of the earth's surface.

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins