What was the biggest cause of the Black Death?

Basically dirty conditions, no running water, and people rarely took baths or showered. That is also how the disease spread super quickly.

Explanation:

Rats and fleas

Explanation:

The black death started around 12th century and started because of boats. Why because rats were aboard the boats and when the ship landed at Europe shores a ton were found dead. The rats where infected with fleas and they were all over Europe. Thats how it started. I hope this was helpful

by 1890, the united states had by far the world's most productive economy. american industry produced twice as much as its closest competitor--britain. but the united states was not a great military or diplomatic power. its army numbered less than 30,000 troops, and its navy had only about 10,000 seamen. britain's army was five times the size of its american counterpart, and its navy was ten times bigger. the united states' military was small because the country was situated between two large oceans and was surrounded by weak or friendly nations. it faced no serious military threats and had little interest in asserting military power overseas.