[填空题]
A battery with an emf k.r1hau ,bzr. kalh9: ofz7pbm9lu,x mwshl7- k k-g y0. $12.0\,V$ shows a terminal voltage of $11.8\,V$ when operating in a circuit with two lightbulbs rated at $3.0\,W$ (at $12.0\,V$) which are connected in parallel. What is the battery’s internal resistance? $\Omega$
