某公司的销售收入状态如表所示，就销售收入而言该公司的盈亏平衡点是（）百万元人民币。某

沿水平方向用力推讲台，但没有推动，这表明讲台受到地面对它的 ______摩擦力．如果讲台推动起来了，表明讲台受到地面对它的 ______摩擦力．（均选填“滑动”或“静”）

下列关于北电BTS9000DDM模块的功能描述错误的为（）。

A.为接收链接提供前台低噪音放大

B.TX和RX耦合、滤波

C.将收到的信号解密、均衡、然后解调

D.TX/RX隔离

撤热水管经化学处理后，内壁会（）。

A、有所腐蚀

B、结垢

C、形成保护膜

D、无变化

MIDI enables people to use (51) computers and electronic musical instruments. There are actually three components to MIDI, the communications " (52) ", the Hardware Interface and a distribution (53) called "Standard MIDI Files". In the context of the WWW, the most interesting component is the (54) Format. In principle, MIDI files contain sequences of MIDI Protocol messages. However, when MIDI Protocol (55) are stored in MIDI files, the events are also time-stamped for playback in the proper sequence. Music delivered by MIDI files is the most common use of MIDI today.

（52）是（）

A.device

B.protocol

C.network

D.controller

厌食而兼嗳气酸腐、脘腹胀满属于（）

A.脾胃虚弱

B.湿盛困脾

C.食滞胃脘

D.肝胆湿热

E.妊娠恶阻