《论自由》一书的作者是()。 ["穆勒","弥尔顿","洛克","杰弗逊"]
大流量采样器采集环境空气样品时,采样口的抽气速度为()m/s。 ["0.1","0.3","0.5","0.7"]
Langston Hughes was noted for his() ["true description of urban Blacks in poetry","unconventional portrayal of Harlem","singing of black America","None of the above"]
心理旋转
留在唱片、录音带上的声频信息和摄在胶卷、录像带上的视频信号统称为() ["光盘","磁带","声像信息","多媒体"]
区域创新网络包括以下几个组成要素:()、()、()、()、()。