【单选题】在各项都为正数的等比数列{a n }中,a 1 =2,a 6 =a 1 a 2 a 3 ,则公比q的值为( )
【单选题】---Have you ever read the book Homeless to Harvard?
A.
- Liz Murray is really great. It __________ her only two years to finish what other students spent four years on.
【单选题】在各项都为正数的等比数列{an}中,首项a1=3,前三项和为21,则a3+a4+a5=( ).
【多选题】多选:下列公用企业的行为,哪些属于限制竞争行为( )?
A.
电信部门要求市话用户使用某一指定品牌的装机电话