计算:﹣17+8=____
下面的说法对吗?
1435 中因为35含有质因数7,所以不能化成有限小数.
The students are required by the teacher________ more attention to their handwriting.
某线圈通有如图所示的电流,则线圈中自感电动势改变方向的时刻有( )