Which of the following do NOT describe an element? 1. A mixture of different chemicals
2. Represented by a symbol that contains one uppercase letter
3. Represented by a symbol that can contain a second uppercase
letter
4. Represented by a symbol that can contain a lower case letter
5. A pure substance
6. Can be identified using the periodic table

rain is the best answer

it's c. (to reduce the greenhouse effect/carbon gasses)

when the displaced particles are perpendicular to the direction the wave travels, is called a transverse wave, whereas in longitudinal wave the displace practices are parallel to the direction of the wave.

in the given image:

first image shows - longitudinal wave

second image shows - transverse wave

third image shows - longitudinal wave

fourth image shows - longitudinal wave