Five books are arranged on a shelf: P, Q, R, S, and T. R is to the left of Q but to the right of P. S is to the right of T. Which book is at the extreme right?
There are four boxes labeled A, B, C, and D. Box A contains apples, Box B contains bananas, Box C contains cherries, and Box D is empty. If Box A is heavier than Box B and Box C is lighter than Box A, which box is the lightest?