If the long chord and tangent length of a circular curve of radius R are equal the angle of deflection, is

If the long chord and tangent length of a circular curve of radius R a

1.	If the long chord and tangent length of a circular curve of radius R are equal the angle of deflection, is
A.	30
B.	60
C.	90
D.	120
E.	150 .
Answer» E. 150 .