What is the difference between a specification limit and a control limit?

Part 1.What is the difference between a specification limit and a control limit?

What is the sigma of this process, and how many doses would be above 5 mg in 1,000,000 doses produced? What would this mean for real patients in terms of underdosing or overdosing?

Part 3. Which pharmaceutical manufacturing process below process is ‘capable?’ In other words, which process is a 6 sigma or better process?