Answer:
the answer is b
Explanation:
Physical changes affect a substance's physical properties but do not alter its chemical structure. Types of physical changes include boiling, clouding, dissolution, freezing, freeze-drying, frost, liquefaction, melting, smoke and vaporization.
The hydrosphere<span> includes water that is on the surface of the planet, underground, and in the air. A planet's </span>hydrosphere<span> can be liquid, vapor, or ice. On </span>Earth<span>, liquid water exists on the surface in the form of oceans, lakes, and rivers.</span>
covalent bond is the answer.
Answer:
Gamma, Infrared,microwave,Radio, visible, ultraviolet,X-ray