How many delegates present at the convention signed the constitution on september 17, 1787?
a. 50
c. 29
b. 42
d. 39

This question is extremely tricky. I might be wrong, but let's give it a shot.
There were 55 delegates present. Of the 55 delegates, only 41 signed their names of the constitution.. However!!! John Dickinson of Delaware was not present at the time, so he had George Read sign it for him. Making it only 39 delegates who actually physically signed the constitution. I think it is D.. 39

To have a bunch of countries to team up, and communicate not let the communist break them apart and take over the world

The answer is william henry harrison pursued and defeated british forces retreating into canada.