Helga Was Charged in 1987 with the Theft of Confidential

Helga was charged in 1987 with the theft of confidential information in Vancouver.The only case at the time that was relevant was one in which the Ontario Court of Appeal said that the defendant,in a situation identical to Helga's,was guilty of theft.
A)Discuss how the theory of precedent applies here.
B)If the defendant in the Ontario case appealed and,in the summer of 1988,before Helga's case had come to trial,the Supreme Court of Canada reversed the Ontario Court of Appeal's decision,would this change your answer to the previous question? Why or why not?