Which statements about water are true? Choose more than one answer. Water molecules have no subatomic particles
Water does not appear on the periodic table of elements
Water molecules contain a lot of empty space
Molecules of water cannot be broken apart
Hydrogen and oxygen have different properties when separated
Every molecule of water contains two atoms of oxygen

Will you chech and finish these for me, because i am stumped with them.

Waves are used in many practical applications to support work, entertainment, and health. one example is the use of ultrasound imaging to safely track the development of a growing fetus. what is a specific example of a practical application of waves in medicine, entertainment, safety, or other fields? provide a brief explanation of how the properties of waves are useful to that application.

Convection currents are caused by differences in what two things?