What is hard water and what is soft water

Water that is "hard" contains a certain amount of dissolved minerals (like calcium and magnesium). 
Water that is "soft" is a certain type of treated water. It contains only one type of ion, which is sodium. An example of this is rainwater because it is naturally soft water.

Hard water... is water that contains an obvious amount of broke down minerals (like calcium and magnesium). Delicate water... is dealt with water in which the main particle is sodium. As water falls, it is normally delicate. ... Then again, delicate water tastes salty and is some of the time not reasonable for drinking.

Explanation:

(1) A sound wave a mechanical wave because mechanical waves rely on particle interaction to transport their energy, they cannot travel through regions of space that are void of particles. Sound is a mechanical wave and cannot travel through a vacuum. These particle-to-particle, mechanical vibrations of sound conductance qualify sound waves as mechanical waves. Sound energy, or energy associated with the vibrations created by a vibrating source, requires a medium to travel, which makes sound energy a mechanical wave. The answer is(B) it travels in the medium.

(2) An ocean wave is an example of a mechanical transverse wave

The compression is the part of the compressional wave where the particles are crowded together. The rarefaction is the part of the compressional wave where the particles are spread apart. The answer is (C) Compression.