Answer: May 25, 1787, freshly spread dirt covered the cobblestone street in front of the Pennsylvania State House, protecting the men inside from the sound of passing carriages and carts. Guards stood at the entrances to ensure that the curious were kept at a distance. Robert Morris of Pennsylvania, the "financier" of the Revolution, opened the proceedings with a nomination--Gen. George Washington for the presidency of the Constitutional Convention. The vote was unanimous. With characteristic ceremonial modesty, the general expressed his embarrassment at his lack of qualifications to preside over such an august body and apologized for any errors into which he might fall in the course of its deliberations. To many of those assembled, especially to the small, boyish-looking, 36-year-old delegate from Virginia, James Madison, the general's mere presence boded well for the convention, for the illustrious Washington gave to the gathering an air of importance and legitimacy But his decision to attend the convention had been an agonizing one. The Father of the Country had almost remained at home. Suffering from rheumatism, despondent over the loss of a brother, absorbed in the management of Mount Vernon, and doubting that the convention would accomplish very much or that many men of stature would attend, Washington delayed accepting the invitation to attend for several months. Torn between the hazards of lending his reputation to a gathering perhaps doomed to failure and the chance that the public would view his reluctance to attend with a critical eye, the general finally agreed to make the trip. James Madison was pleased.
Unlike Britain, France, Russia and the United States wanted to keep trade in China open. It might be added that it was the U.S who implemented the "Open Door Policy" with China in the first place.
Disease had the most impact as the result of Columbian exchange because due to this exchange deadly diseases spread across all over the world with the travel and migration of people.
Columbian exchange was as exchange of plants, animals, humans, culture, disease, technology and other things to the Africa, America and many other countries. The Columbian exchange had negative as well as positive impact on both the continents.
Impact on Europe:
This exchange benefited the old world with the introduction of "new world crops" such as corn and potatoes. This exchange had negative impact as well. The transmission of epidemics and African people into slavery were some of negative impacts of Columbian exchange.
Impact on America:
The technology helped in advancement in agriculture and food cultivation while the exchange of disease increased the mortality rate among the Americans.
I believe it was the crusades, which was attacking for the land known as "Jesus's birthplace", need anything, tag me :)
