滑模系统中的施工平台必须有可靠和必要的（）。
A．强度
B．刚度
C．强度及刚度
D．水平度
参考答案：C
电泵井选泵所需要的资料有哪些？
Quebec, once originally ______ by France, ______ the British in 1763.
A．being colonized; was lost in
B．was colonized; was lost to
C．colonized; was lost to
D．having being colonized; was lost in
