A. Tell whether the set is well-defined or not. Write WD for well-defined and NWD for not well-
defined. (5 pts
1. The set of multiples of five greater than 10 but less than 50.
2. The set of popular actresses.
3. The set of delicious foods.
4. The set of even numbers less than 21.
5. The set of factors of 24.​