A. The working principle of pressure cooker is that the boiling point rises with the increase of pressure, which has nothing to do with the characteristics of liquid pressure. This option is wrong;

B the plastic sucker hook is fixed on the wall by atmospheric pressure. This option is correct;

C. Lift the plate from the top of the table and apply upward force. The plate moves a certain distance, so work is done on the plate. This option is correct;

D, the rated power of the induction cooker is certain, and has nothing to do with working hours. This option is wrong.

So choose b and C.