解;(1)∵P额=U额I额 ∴I额=P额/U额=550w/220V=2.5A
又∵I额=U额/R ∴R=U额/I额=220V/2.5A=88Ω
(2)W=Pt=550w×12×60s=396000J=0.11Kw/h