同15圆内最长的线段是直径．______．
因为直径是通过圆心，并且两端都在圆上的线段，
所以直径长是圆里最长的线段正确．
故答案为：正确．
磨牙支托的宽度应为磨牙面颊舌径的（）。
A.1/3
B.1/2
C.2/3
D.1/4
E.3/5
Hurry up, honey! We have to arrive at the airport by 11:00 o’clock, _____ we will miss the flight.
A．however
B．instead
C．anyway
D．otherwise
支托的宽度应为磨牙