a) The total central angle of a circle is 360 degrees.
Therefore, the angle of the shaded area is,

Therefore, the angle of the shaded area is 240 degrees.
b) The percent of the circle shaded is,

Therefore, the percent of the circle shaded is 66.67%.
c) The fraction of the circle shaded is,

Therefore, the fraction of the circle shaded is 2/3.