【单选题】why did the author tell her brother “make sure the band can play waltzes and polkas”?
A.
she wants to dance with her father once more.
B.
her father can only dance those music.
C.
she wants to listen to such kind of music in the party.
D.
few band can play Waltze and Polkers.
【简答题】A. He wants to learn to play the violin. B. His band will perform. next week. C. He wants to play in the band. D. He can't play the violin well.
【单选题】采用简单移动平均法测定长期趋势,假设移动项数k=4,则2002年产量的移动平均数是( )。
【判断题】平均趋势法的优点在于既考虑了销售量的移动平均数,又考虑了趋势值的移动平均数,缺点是这种方法较为复杂。 ( )
【判断题】滤波器、模拟锁相法和数字锁相法都属于位同步中的外同步法范畴。