Tiana is skiing along a circular ski trail that has a radius of 2.8 km. She starts at the 3-o'clock position and travels in the CCW direction. Tiana stops skiing when she is 1.951 km to the right and 2.009 km above the center of the ski trail. Imagine an angle with its vertex at the center of the circular ski trail that subtends Tiana's path. a. How many radians has the angle swept out since Tiana started skiing? b. How many km has Tiana skied since she started skiing?