The correct answer is belief.
A philosophical assumption means that the philosopher just assumes, or believes something to be true, without any concrete evidence. The moment he or she is able to provide proof to support his or her assumption, it becomes a law because it can be checked if necessary.
Answer: "Philadelphia and New York City were the most populated cities in 1860 and would soon reach one million residents."
Explanation: This sentence stands out as it is a detail that is a bit more loosely related and can be removed without affecting the overall flow of the passage. This is an unnecessary detail and sounds odd as the author already mentioned that cities were growing quickly, so it is not necessary and the rest of the passage still sounds good without this part and still is interesting.
URLs ending in .gov, .org or .edu are considered to be reliable sources when writing an informative essay because these sites are from educational institutes, government and non-profit organizations which data is considered to be from trustworthy and unbiased sources.
Answer: they went through a lot of bad stuff.
Explanation: