小李在解方程5a﹣x=13(x为未知数)时,误将﹣x看作+x,得方程的解为x=﹣2,则原方程的解为[ ]
A.x=0
B.x=1
C.x=2
D.x=3
答案:C
It is by no means clear _______ the president can do to end the strike.[ ]
A. how
B. which
C. that
D. what
当天线平行于地面时,天线辐射电磁波的电场也平行于地平面,对地平面来说就叫()。
A.水平极化波
B.垂直极化波
C.椭圆极化波