Q. Read the following information carefully and answer the question which follow: If ' A x B’ means ‘A is sister of B’. If ‘A + B' means ‘A is the mother of B'. If ‘A ÷ B' means ' A is daughter ‘of B'. If ‘A- B’ means ‘A is father of B’. If P + R ? T - Q ÷ S + U, then how is S related to T ?