who was chosen as this president?
George Washington
Constitutional Convention (United States)
The first thing the Convention did was choose a presiding officer, unanimously electing George Washington president of the convention. 
what were the plans proposed at the constitutional convention New Jersey Plan and Alexander Hamilton's plan what was proposed in the former one? The Confederation Congress would remain unicameral with each state having one vote and Congress would be allowed to levy tariffs and other taxes as well as regulate trade and commerce when was it laid down? June 15, 1787 what were the operations of the above convention? The first thing the Convention did was choose a presiding officer and the Convention then adopted rules to govern its proceedings
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Constitutional Convention (United States) [SEP] Operations and procedures
If too few of a state's delegates were in attendance, the state did not cast a vote. After two of New York's three delegates abandoned the convention in mid-July with no intention of returning, New York was left unable to vote on any further proposals at the convention, although Alexander Hamilton would continue to periodically attend and occasionally to speak during the debates.