How many days did it take for Mehmed the Conqueror and his
janissaries to assume total control
of Constantinople?

it took two months so around 55 days to conquer Constantinople.

Explanation:

they had better weapons

they believed democracy was worth the fight

powers  are  denied  to the  national governmentin three distinct ways: some  powers, such as the  power  to levy duties on exports or prohibit the freedom of religion, speech, press, or assembly, are expressly  denied  to the  national government  in the  constitution.