________ recent report stated that the number of Spanish speakers in the U．S.would be higher than the number of English speakers by ________ year 2090.

A．A；the

B．A；/

C．The；/

D．The；a

原始数据都乘以一个不等于0的常数k（）

A.均数不变

B.均数大小不定

C.均数变为k倍

D.均数增加k倍

E.均数减少k倍