1. How can Murarka find out if the process involved in the premium express scheme is under statistical control? 

 2. What is meant by random causes and assignable causes of variation? List a few conditions when it becomes imperative to carefully investigate process variations even if the process is under statistical control.  

3. How can Murarka identify the potential causes for the delay in the delivery of the shipments booked under the premium express scheme? Explain and show related methods.