贵州下列被评为国家AAAA级旅游景区的是()。
A、黄果树风景名胜区
B、黔灵公园
C、花溪公园
D、遵义会议会址
参考答案:A, B, D
It was several minutes before I was ______of what was happening.
A.aware
B.accused
C.tired
D.a shamed
若反馈信号与原系统输入信号的方向相反则为()。