能耗制动是将运转中的电动机与电源断开并改接为发电机,使电能在其绕组中消耗的一种电制动方式。( )
参考答案:对
Modern education is _____ sitting at a desk and looking at the blackboard.
A.no more than
B.not less than
C.more than
D.less than
已知二次函数y=ax2+bx+c(a≠0)的图象过0(0,0),A(1,-1),B(-2,14)和C(2,m)四点.求这个函数的解析式及m的值.