<em><u>Lack of sanitation,</u></em><em> </em><em><u>ineffective treatments</u></em>, and <em><u>increase of rats and fleas</u></em> are the contributors. The other three are the effects.
<span>Ogodei Khan oversaw the greatest territorial expansion of mongol histroy</span>
It allowed the US to trade with other country's and it created a war
I'm not too sure but I think it freed all slaves living in states that seceded from the union.. final answer is D