Answer:
1859
Explanation: Petroleum became a major industry following the oil discovery at Oil Creek, Pennsylvania, in 1859. For much of the 19th and 20th centuries, the US was the largest oil producing country in the world.
Answer:
Jobs in factories, volunteered with Red Cross, and served in the military.
Explanation:
More than six million women took wartime jobs in factories, three million volunteered with the Red Cross, and over 200,000 served in the military.
When he saw the apple falling beside him, he start thinking : how and why the apple keeps falling down? What attracts the apple to the ground? After much research, he conclued that the Earth has a gravity like any planet or cosmic object. This gravity pulls objects towards the ground, allowing the existence of an atmosphere and preventing items from floating in the air. This scientific discovery has changed dramatically science in that time and it allowed us to invent machines that defy the law of gravity.
