Ineed figuring out the radius. i need finding the angle.

To find the radius, draw an auxiliary line from the center to the endpoint of the line with a distance of 28. This will create a right triangle. Using Pythagorean Theorem we can find the length of the hypotenuse, which happens to also be the radius!
*Remember that a radius that is perpendicular to a chord bisects it. 

14 squared + 8 squared = radius squared
196 + 64 = 260
radius = square root of 260 = 16.1
Final x = 16.1

The measure of angle O is 56. The measure of angle R would equal the measure of angle O if O had been an inscribed angled since angles that intercept the same arc are congruent. However, angle O is a central angle, therefore, it has double the degree as an inscribed angle.