An automated tube bending operation produces parts with an included angle = 91.2°. The process is in statistical control. and the values of included angle are normally distributed with a standard deviation = 0.55°. The design specification on the angle = 90.0° ± 2.0°. (a) Determine the process capability. (b) If the process could be adjusted so that its mean = 90.0°, determine the value of the process capability index.