题目

.Who is it up __________the first company __________is run by the state? A .to take charge of；which        B .to  to  take charge of；that C. for to take charge of；that       D. to  to  taking charge of；which 答案：B关于机械能，下列说法中正确的是（ ）A．汽车匀速下坡机械能不变B．人造地球卫星在远地点势能最小C．带动钟表转动的发条，将势能转化为动能D．运动的物体只有动能