QuestionReportQuestion: If A ∩ B = B, then...If A ∩ B = B, thenAA⊂BA \subset BA⊂BBB⊂AB \subset AB⊂ACA=ϕA = \phiA=ϕDB=ϕB = \phiB=ϕAnswerB⊂AB \subset AB⊂AExplanationSolutionSince A∩B=B,∴B⊂AA \cap B = B , \quad \therefore B \subset AA∩B=B,∴B⊂A.