Direction: There are seven students R, S, T, U, V, X and Y. All of them go to the library in a week starting from Monday to Sunday (of the same week) but not necessarily in the same order. Only one student goes to the library on each day. T goes to the library one of the days before on Wednesday. Two students go to the library between T and X. Only one student goes to the library between X and V. Two students go to the library between V and R. Only one students go to the library between R and Y. Two students go to the library between S and U. U does not go to the library on Wednesday.

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Four of the following five are alike in a certain way and so form a group. Which of the following does not belong to that group?