A. Adam hired Sally to install double glazing in his house. They agreed that Sally would fit 6 windows for $1,000. After Sally fitted 4 windows, she realized that the work was a lot more demanding than originally anticipated. She notified Adam that she would need another $200 in order to finish the work before the summer rains started. Adam, concerned that his house might be damaged if the work was delayed, agreed to pay the extra amount. Sally finished the work and invoiced Adam for $1,200. Adam is reluctant to pay the additional $200. Advise Adam of his legal options. (20 marks)