The shaded portion of the circle is the smaller sector whose radius is the same as the radius of the circle which is given as 4 units. The sector is always bounded by two radii with a common point which is the center of the circle and forming an angle at that point. The given sector forms an angle of 45 degrees.
Area of a sector is expressed as
#/360 × π × r^2 and # is in degrees
Therefore, area of the shaded portion or sector = 45/360 × π × 4^2
The answer is c because of the fact that if the 2 angles at 55 and 20 that means that you have to add them together and get to 180 for the triangle to be true
