300
When the children let Bernard sell the popcorn and keep the money, Bernard was glad to have the money and felt proud of himself for working for it. If the children had sold the popcorn and given Bernard the money, he would have been glad to have the money but ashamed because he hadn't worked to earn it.
What is: compare and contrast how Bernard felt about selling popcorn to how he would have felt if John, Clara, and Harry had given him the money?