Fossil fuels has been used more in the existing world. Why?

fossil fuels are being used more because fossil fuels are of great importance because they can burn to produce a  significant amount of energy per unit mass the use of coal as a fuel prefates recorded history.

Explanation:

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adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.

an electric circuit