【简答题】A.Took balanced meals with champagne. B.Ate vegetables and fruit only. C.Refrained from fish or meat. D.Avoided eating rich food.
【单选题】Since she’s on a diet, Stella refrained from eating a second piece of carrot cake.
【判断题】One mother refrained from posting her son's photos online when she considered the matter from her son's perspective. (10.0分)A. √ B. ╳
【单选题】按心理学派常将心理治疗分为四大类,下列哪一类不属于心理治疗( )
【简答题】A.πA,B,C(σA<C(R×S)) B.πR.A,R.B,R.C(σR.A<S.B(R×S)) C.πR.A,S.B,S.C(σR.A<S.C(R×S) D.πS.A,S.B,R.C(σR.A<S.C(R×S))
【简答题】设A={a,b,c},A上的关系R和S定义如下: R={〈a,b〉,〈b,b〉,〈b,c〉},S={〈a,c〉,〈b,c〉,〈c,c〉}, 求关系R∪S,R∩S,R-S,S-R,R S.
【多选题】根据系统和环境的联系方式可将系统划分( )