Thanks for the help everyone so far, unfortunately the assignment descriptive was quite vague which has meant I've not really been able to specify my question properly.
As an additional question, would the application of using the ECON mode within the aircraft's FMC have any further effect time and/or fuel saving? I understand that ECON mode is related to Cost Index & is acquired by an algorithm, but but how would one describe the factors that influence ECON mode?