Why was the discovery of large amounts of coal a cause of the Industrial Revolution? A
The smoke from burning coal harmed people's health.

B
The discovery of coal caused a spike in population.

C
Coal-powered cars moved faster than railways.

D
People could use coal to power factories.

Which of the following describes an effect of world war ll on the united states economy a. automobile companies produced a record number of cars b. many factories had to expand to produce military equipment c. the airplane industry suffered as the allies began using airplanes in combat d.cities with shipyards declined because so many ships had been sent overseas.