Ernest Rutherford contributed to the atomic theory by discovering that the atom is mostly empty space.
He can to that conclusion because he fired alpha particles at gold foil, which was so thin that it was only around .00004 cm thick, and while almost all shot straight through, some actually bounced back!
He likened it to shooting a 15-inch round(bullet) at tissue paper, only to have it bounce right back at you! Based on this, he theorized that the atom is mostly empty, which is why a majority of the particles passed right through, but in the very center of the atom there is a super-dense structure called a nucleus that held a majority of the atom's mass. This super-dense mass would be more than massive enough to deflect the particle, should they collide.
The correct answer here is the last option
Mahan argues clearly that a strong navy is required in order for United States to expand far beyond its shores and its territory in order to become a super power. Manifest Destiny is a belief that first referred to the destiny of the settlers to spread across North America and later beyond. Here Mahan says that in order to do that the government needs to provide supply points for its navy.
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Answer:
This story is set on the planet Venus, where the sun shines for only two hours once every seven years. It opens on the day that the sun is due to make its appearance once again. Margot and the other children in her school on Venus are nine years old. Margot came from Earth to Venus five years ago.
Explanation:
The Missouri Compromise of 1820 established the latitude 36°30′ as the northern limit for slavery to be legal in the territories of the west.
Explanation:
- The Missouri Compromise, as it was known, would remain in impact for just over 30 years till the Kansas-Nebraska act of 1854 revoked it.
- In 1857, the Supreme Court in Dred Scott's case found the agreement unconstitutional, setting the stage for the nation's final journey through the Civil War.
- In 1820, while growing sectional tensions over the slavery issue, the U.S. Congress passed a law welcoming Missouri to the Union as a captive state and free state.
