Answer:
The circumference of a circle is calculated using the formula `C = 2πr`, where `r` is the radius of the circle. Since you have given the radius as 4 and asked to use 3.14 for π, we can calculate the circumference as `C = 2 x 3.14 x 4 = 25.12`.
The area of a circle is calculated using the formula `A = πr^2`, where `r` is the radius of the circle. Using the same values for π and r as before, we can calculate the area as `A = 3.14 x (4)^2 = 50.24`.
So, for a circle with a diameter of 8 and a radius of 4 (using 3.14 for π), its circumference is approximately **25.12** and its area is approximately **50.24**.