4. Compare and contrast a mechanical wave and an elec-
tromagnetic wave.
How are they similar and different

difference:

1. The generation mechanism is different, the mechanical wave is generated by mechanical vibration; the electromagnetic wave generation mechanism is also different, there is the periodic movement of electrons (radio waves); the outer electrons with atoms are generated after being excited (infrared, visible, ultraviolet) The inner electrons with atoms are generated after excitation (roentgen rays); the nuclei with atoms are generated after excitation (gamma rays).

2. The propagation mechanism is different: the mechanical interaction between the particles and the alternating induction of the electromagnetic field.

3. Mechanical waves have both transverse waves and longitudinal waves; electromagnetic waves are material waves and belong to transverse waves.

4. The influence of the medium on the propagation speed is different

Explanation:

https://qiaodahai.com/similarities-and-differences-between-mechanical-waves-and-electromagnetic-waves.html

one would be wind another would be water density

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.