Which is not the prime number

- Which of the following is not the prime number
- Which one is not prime number
- Which one of the following is not the prime number
- Which are not prime numbers of 70
- Which are not prime numbers of 42
- Which of the following is not prime numbers
- Which of the given is not a prime number
- Which of the following numbers is not prime number
- Find the number which is not a prime number