For each phrase below, decide if it would be used to create a primary $($or optimizing$)$ equation or the secondary $($constraint$)$ equation.

Question $2$ options:

$12$

You have $500$ feet of fencing

$12$

Closest point

$12$

Largest enclosure to hold the cattle.

$12$

Minimum cost

$12$

Box must hold $500$in$3$

$1.$

Primary $($optimizing$)$

$2.$

Secondary $($constraint$)$