A class consists of six students: P, Q, R, S, T, and U. The selection criteria are: 1) P cannot be selected if Q is selected. 2) R must be selected if S is selected. 3) T can be selected only if U is not selected. Which of the following combinations is valid?
A selection of fruits consists of apples, bananas, cherries, and dates. The selection criteria are: 1) Apples cannot be selected if bananas are selected. 2) Cherries must be included if dates are included. Which of the following selections is valid?