im giving you instrutions to get the answer its simple:D
The figure above shows a circular sector OAB , subtending an angle of θ radians ... The points A and B lie on the circle so that the angle AOB is 1.8 radians. .... c) Calculate the smallest angle of the triangleABC , giving the answer in degrees, .... Given that the length of the arc AB is 48 cm , find the area of the shaded region.