From statement I, if the first Sunday is the 5th, subsequent Sundays are on the 12th, 19th, and 26th. Thus, the last Sunday is the 26th. From statement II, if March 31st was a Friday, then March 26th (5 days earlier) was a Sunday, making it the last one. Therefore, either statement is sufficient. [cite: 1, 1769, 1772]