1.Who isa hero who controls the floods in Chinese history?
A、A The Great Yu
B、B Yu the Great
C、C The Yu Great
D、D All the people

A.居住区
B.水环境
C.生态敏感目标（水生、陆生）
D.水土流失防治

A．制动不灵
B．制动拖滞
C．制动噪音
D．制动跑偏