Could you please teach me _______ the computer?
A:how check
B:to check
C:how to check
D:to how checking
在下列几种估测中,最接近实际值的是( )
如图,⊙O是△ABC的外接圆,AB是⊙O的直径,D为⊙O上一点,OD⊥AC,垂足为E,连接BD