Final answer:
The quadrant that contains A. -11pi/18 is II and the reference angle is 11pi/18.
Step-by-step explanation:
The given angle is -11pi/18. To determine the quadrant that contains this angle and find the reference angle, we need to convert the angle to its positive equivalent within the range of 0 to 2pi (or 0 to 360 degrees).
The positive equivalent of -11pi/18 is 7pi/18.
Since 7pi/18 falls in the second quadrant (between pi/2 and pi), the answer is option A- II 7pi/18.
The reference angle, which is the positive angle between the terminal side and the x-axis, can be found by subtracting 7pi/18 from pi.
So, the reference angle is pi - 7pi/18 = 11pi/18.