— I suggest buying her a Teddy Bear for her birthday. —_____someone else brings the same present?
A:If
B:What
C:What if
D:How about
如图所示,理想变压器原线圈的匝数n1=1100匝,副线圈的匝数n2=110匝,R0、R1、R2均为定值电阻,且R0=R1=R2,电流表、电压表均为理想电表.原线圈接u=220 2 sin(314t) (V)的交流电源.起初开关S处于断开状态.下列说法中正确的是( )
位似图形上任意一对对应点到 ____的距离之比等于位似比.
一根绳子可围成一个半径是6米的圆,若用它围成一个正三角形,那么它的边长是( )米