Answer:
Here we are supposed to know the diameter of the circle, d, but the question seems incomplete.
I will solve this for a general diameter d.
First, we know that for a circle of radius R, the perimeter of a circle is:
P = 2*pi*R
where pi = 3.14
And we know that the diameter is twice the radius, then:
2*R = d
isolating R we get:
R = d/2
If we replace this in the perimeter equation we get:
P = 2*pi*R = 2*pi*(d/2) = pi*d
Then the perimeter of a circle with diameter d is:
P = pi*d = 3.14*d
Where to find the perimeter of a specific circle, you just need to replace the variable "d" with the actual diameter of the circle.