A:4x2﹣1
B:1﹣4x2
C:﹣4x2+4x﹣1
D:4x2﹣4x+1
如图所示,在O点放置正点电荷Q,a、b两点的连线过O点,且Oa=ab,以下说法正确的是( )
找出不同类的单词。
Wang Tao ______ makes large pieces of metal art_____ makes smaller pieces for the home.