甲欠乙10万元租金，乙欠甲10万货款，两债均到履行期，甲以书面形式通知乙，以致双方债务关系消灭，合同法理论称此为( )A、免除B、提存C、抵销D、混同

梯段相邻踏步高差应不大于每踏步两端宽度差不大于（ ）mm。A.10B.12C.15D.20

单项选择题梯段相邻踏步高差应不大于每踏步两端宽度差不大于（ ）mm。

向上运动时，b点 （　　）A.经过平衡位置向上运动B.处于平衡位置上方位移最大处C.经过平衡位置向下运动D.处...

单项选择题
向上运动时，b点 （　　）

The narrator's friend strongly advise him never to driv...

单项选择题The narrator's friend strongly advise him never to drive across through the desert because __________. A.
He was not good at driving. B.
His car would surely break down in the desert. C.
It would be very dangerous if he met a Bushman. D.
There was no water in the desert.