如图,将矩形纸带ABCD,沿EF折叠后,C、D两点分别落在C′、D′的位置,经测量得∠EFB=65°,则∠AED′的度数是( )
A:65°
B:55°
C:50°
D:25°
关于放射性元素的半衰期,下列说法中正确的是( )
Linda's parents gave her ______ advice on how to make friends with others.
下列事实或现象属于光的反射的是( )