For each $n \in \mathbb{n}$, let $a_n = [n] \times [n]$. define $b = \bigcup_{n \in \mathbb{n}} a_n$. does $b = \mathbb{n} \times \mathbb{n}$? either prove that it does, or show why it does not.

No, it is not.

Step-by-step explanation:

The set contains every ordered pair of Natural numbers, while B only contains those pairs in which both values in each entry are the same. Therefore, C is a bigger set than B, but B is not equal to C because for example C contains and B doesnt because 1 is not equal to 2.

number one is the correct answer

step-by-step explanation: dogs and cats are mentioned, no other animals