¿Como se sabe desde las ciencias que la vida tuvo un origen en la tierra?

Kublai khan honored his mongol heritage by: a)marring only one wife b)praying facing mecca five times a day c)slaughtering ten chinese officials every year d)building a large enclosed hunting ground at shangdu,his summer palace

In italy, the distance between milan in the north and palermo,sicily, in the south is about 550 miles. in the united states, the distance betweenboston, massachusetts, and savannah, georgia, is about 900 miles. do you think the american revolutionaries of 1776 in the 13 colonies faced some of the same challenges as the patriots who struggled for italian unity in the 1860s?  

What has been a long term effect on the panama canal