Write each set in the indicated form. If you need to use "
…" to indicate a pattern, make sure to list at least the first four elements of the set.

a. Set-builder form: {y | y is a natural number and 12 ≤ y ≤ 15}

Or

{y | y is a natural number and 11 < y < 16}

b. Rooster form: {3, 4, 5 ,6, ...}

Step-by-step explanation:

a. Rooster form: {12, 13, 14, 15}

All four numbers are natural numbers, therefore we would write this set of numbers in set builder form such that they will all have the same property. Thus:

Set-builder form: {y | y is a natural number and 12 ≤ y ≤ 15}

Or as

{y | y is a natural number and 11 < y < 16}

b. Set-builder form: {y | y is a natural number and y > 2}

Since natural numbers are positive integers, this tells us that all values of the set are not less than or equal to 2. Therefore, they are integers that range from 3 and above.

Thus:

Rooster form: {3, 4, 5 ,6, ...}