下滑时，飞机重量越大（）
A、升阻比越小
B、最小下降角速度减小
C、对下滑性能无影响
参考答案：B
I could hardly tell the twins apart because their appearances are only ____ different.
A．slightly
B．gradually
C．personally
D．extremely
依据现行的《工程测量规范》规定：实际地下管线的线位与邻近地上建(构)筑物、道路中心线或相邻管线的间距中误差不超过图上______mm。
A．0.3 B．0.4 C．0.5 D．0.6
