The main function of the human digestive system is to

Digest food, and to keep the main functions together

Information on the cost of things, quantitative data has to do with numbers, qualitative data uses details such as taste, appearance, what it looks like etc. 

Iwould suggest the myers-briggs type indicator because the railroad unions are looking for which are focused introverts. the mbti was designed to provide a lot of information about what a person likes and what their personality based on the four-dimension scale. also for an employer it has been extremely to predict how an employee would act in a professional setting. this is what the railroad unions are looking for. they want the railroad workers to be focused and skillful to ensure the safety of everyone around them. but the other assessments don't match the criteria for the unions. like the measure disorder, emotions and self-esteem while the rorschach and tat tests are both projective tests that mainly measure someone’s personality. also, because this job is not easy, it is vital to make sure the employers are hiring the right people for the job.