冷饮通常在夏季销量大,在春季和秋季销量一般,在冬季销售量最小。这体现了动态序列的()。
A.长期趋势
B.季节波动
C.不规则波动
D.循环波动
参考答案:B
—When did you ?
—I've for two months. [ ]
A. be married, been married
B. get married, been married
C. get married, got married
警衔等级的设置是警衔制度的核心。警衔设( )等。
A.总警监、副总警监、警监 B.管司C.警督 D.警长