A playground developer has been hired to add a picnic area to the playground. The developer must inscribe a triangular shaped picnic table into circle-shaped grassy area. What is the measure of each arc of the circle?

Step 1 ：The problem is asking for the measure of each arc of the circle. Since the picnic table is triangular, it means the circle is circumscribed about the triangle.

Step 2 ：In a circle circumscribed about a triangle, the measure of each arc is twice the measure of the angle of the triangle it subtends.

Step 3 ：Since the triangle is not specified, we can assume it's an equilateral triangle (as it's the most symmetrical and common in such settings). An equilateral triangle has each angle measuring 60 degrees.

Step 4 ：Therefore, each arc of the circle measures twice this angle, which is 120 degrees.

Step 5 ：Final Answer: The measure of each arc of the circle is \(\boxed{120}\) degrees.