以下光接口代码中,哪些是STM-1速率的?()
A.I-1
B.S-4.1
C.S-16.2
D.L-1.1
E.L-4.2
F.L-16.3
参考答案:A, D
Without proper lessons, you could ________a lot of bad habits when playing the piano.
A.break up
B.pick up
C.catch up
D.give up
简述信用合作社的合作原则。