下列各句中，没有语病的一句是( )

The tall building has ______ floors. And Tony lives on the ______ floor.

He hardly spent any time on his subjects, _________—_________, so he did badly in his lessons.

I must admit you _____________ but I’m afraid the answer is still no

Excuse me. Is the library open all day— . Only from 9 a. m to 4 p.m.