ANSWER
The perimeter is 12 inches.
EXPLANATION
The formula for calculating the perimeter of a square is
[tex]P=4l[/tex]
Since the magnet is in the form of a square, we can use this formula to find the perimeter of the magnet.
It was given that, each side of the magnet is 3 inches long.
Hence, we have l=3 inches.
We have to substitute l=3 into the formula and simplify.
The perimeter is
[tex]P=4 \times 3= 12in.[/tex]