题目

The first people who gave names to hurricanes were those who knew them best — the people of Puerto Rico. The small island of Puerto Rico is in the West Indies, off the coast of Florida. This is where all the hurricanes begin that strike the east coast of the United States. Often they pass near Puerto Rico or cross it on their way north. The people of Puerto Rico expect some of these unwelcome visitors every year. Each one is named after the Saint’s Day on which it arrives. Two of the most destructive storms were the Santo Ana in 1840 and the San Ciriaco in 1899. Giving girls’ names to hu甲数×乙数=800，如果甲数乘2，乙数不变，那么积是______．