The speed of a mechanical wave through a medium depends on the type of medium. It also depends on the type of mechanical wave. Which statement is true?

The statements are;

A) All waves travel at the same speed if no medium is present.

B) Electromagnetic waves require a medium, but mechanical waves do not.

C) All waves travel at the same speed through any medium.

D) Mechanical waves require a medium, but electromagnetic waves do not.

Statement D is true.

Mechanical waves require a medium, but electromagnetic waves do not.

Explanation:

The two types of waves are;

Mechanical waves and Electromagnetic waves.

Mechanical waves require a medium, such as an atmosphere or water, to enable it transport its energy. For example sound waves occur when you clap and thereby distort the air around.

Whereas, Electromagnetic waves do not require a medium to enable it transport its energy. A good example would be light. Normally, Electromagnetic waves are usually formed when the electric field and the magnetic field are perpendicular to each other.

So electromagnetic waves can transmit without a medium because electric and magnetic fields can exist independently without a medium.

explanation:

the largest database of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. the number of potential organic compounds has been estimated at 1060—an astronomically high number. the existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities. the simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. in addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. we use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. the familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. we can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. this leads to differences in geometries and in the hybridization of the carbon orbitals.