Pinguecula, yellowish growths on the surface of the sclera, the white part of the eye, often occur in people who spent a lot of time in the sun. Although most pinguecula occur in middle aged or older people, children can also develop them, All About Vision states.
1 radian = 180 / pi degrees. This cannot be written in the format pi/x. cyberkiwi's answer would be in units of revolution, such that 1 rev is equivalent to a complete circle. Then 1/(2pi) revs would be equivalent to 1 radian.
The radian measure, Î¸, of a central angle is defined as the ratio of the length of the arc. the angle subtends, s, divided by the radius of the circle, r. which gives arc length, s: s = Î¸r. subtend = to be opposite to. One radian is the central angle that subtends an arc length of one radius (s = r).