A family consists of a mother, a father, and two children. The mother is a nurse, the father is an engineer, and one child is a musician. If the other child is not a musician, what is their profession?
There are four animals: a dog, a cat, a bird, and a fish. The dog is a mammal, the cat is a mammal, the bird is not a mammal, and the fish is not a mammal. Which animal is not a mammal?