Question 3 a) Identify and briefly describe THREE (3) basic components of a numerical control system. (6 marks) b) c) As a new engineer to Hero Enterprise, propose an effective technique to grind hypodermic needles for a medical industry. Describe the process in detail with a appropriate illustration. (7 marks) Briefly explain TWO (2) limitations of Scanning Tunnelling Microscope (STM). (4 marks) When a macroscale material been scaled down to microscale, its properties remain the same. However, when the material is scaled down to nanoscale, it undergoes significant changes in its properties. Determine the reasons for these changes to occur. (8 marks) d) (Total: 25 marks)