如图,四边形ABCD是⊙O的内接四边形,∠B=70°,则∠D的度数是( )
A:110°
B:90°
C:70°
D:50°
如图,已知点A,C在反比例函数y=ax(a>0)的图象上,点B,D在反比例函数y=bx(b<0)的图象上,AB∥CD∥x轴,AB,CD在x轴的两侧,AB=3,CD=2,AB与CD的距离为5,则a﹣b的值是 ____ .
如图是由四个大小相同的正方体搭成的几何体,则它的主视图是( )
I've become good friends with several of the students in my school _______ I met in the English speech competition last year.