(i) Because odd numbers are not divisible by two, a set of odd natural numbers divisible by two is a null set.
(ii) Because 2 is an even prime number, the set of even prime numbers is not a null set.
(i) Because odd numbers are not divisible by two, a set of odd natural numbers divisible by two is a null set.
(ii) Because 2 is an even prime number, the set of even prime numbers is not a null set.