Why were some delegates opposed to having a president to lead the executive branch

Those opposed were anti-federalists. This meant that they opposed the federal government having too much power. They though the president being in control would give the federal government too much power.

The delegates were not sure of a President having most of the powers in government. In fact, they thought of dividing the power to three. They also thought that communication and information gathering was too slow. Lastly, the fear of having the majority of votes.

In 911, a group of vikings lead by rollo besieged paris and chartres. after a victory near chartres on 26 august, charles decided to negotiate with rollo. the talks were led by hervé, the archbishop of reims. this resulted in the treaty of saint-clair-sur-epte, which granted rollo and his soldiers all the land between the river epte and the sea. it also granted him brittany, "for his livelihood". at the time, brittany was an independent land which france had not been able to conquer. in exchange, rollo promised the king his loyalty and military assistance when needed. also rollo also agreed to be baptised and to marry gisela, the king's daughter. the territory given rollo is about the same as upper normandy.