涉及到安全的专项交底，须由（）
A、所有接底人签字
B、班组长
C、劳务队长
D、分包经理
参考答案：A
________ arouses his interest can be found in the school library and that is why he goes there ________ happens.
A．No matter what; whatever
B．Whatever; no matter what
C．Anything; no matter what
D．Anything; whatever
按香农定理，如果信号与噪声功率比S/N=1000，带宽B=3000Hz，则数据传输最大速率约为 ______。
A．30Kbps
B．30bps
C．300Kbps
D．3Kbps
