Final answer:
As Washington was preparing for the military operation, evidence suggests that he realized he was trapped and devised a plan to deceive the British. He successfully led his army to leave silently and with cooperation, making it appear that they were still in place.
Step-by-step explanation:
The evidence suggests that as Washington was preparing for the military operation, he realized he was trapped and the British were settling down to work on trenches and believed time was on their side. In response, Washington requested reinforcements from Pennsylvania and devised a plan to have the new troops pretend to be his entire army. Washington's army prepared to leave silently, maintaining unusual cooperation and using deceptive tactics to make it appear that they were still in place. By the time the British realized Washington had left, he and his entire army were already in Manhattan.