Answer:
42mm
Step-by-step explanation:
For the perimeter of a shape you would add all the sides together. So in this case it would be:
7mm+7mm+7mm+7mm+7mm+7mm=42mm
We can solve this problem by dividing 9/12 by 2/12. We should do this because to find how many sets of something are in a number, the question is asking us to do division. Doing this, we get 9/12 * 12/2, giving us our answer of 4.5 sets of 2/12 in 9/12.
Seconds because one second is less than one minute