—Can I talk to the manager?
—Please wait minute.
A:an
B:a
C:the
D:不填
若a<b<0,则下列式子:①a+1<b+2;②ab>1;③a+b<ab;④1a<1b中,正确的有( )
某同学看远处的物体时,其光路如图,则下列说法中正确的是( )