I think the answer is 7mm but I'm not sure.
Have a great day!
Answer:
It works because of the significant principle of piezoelectricity
Explanation:
Using the length given '12 m', because the shape of the object is a square all sides are congruent.
Basically 12+12+12+12=48 or 12 x 4= 48
The answer is 48 m
