What radius of a circle is required to inscribe a square with an apothem if 3.536 inches?

The apothem goes from the centre to mid-point in one of the square sides. if the apothem is 3.536 inthe length of one side of the square is 2 * 3.536 = 7.1 in the diameter of the circle is equalled to the diagonal of the square applying the pythagorean theorema²+ b²= c²  a = b = 7.1 in 2a² = c²  c²= 2 * 7.1²    c²=100.82 c=√100.82    c = 10.1 in the diameter is 10.1 in  the radius r = 5.1 in

You need the internet to you