The amount if prawn caught per week on a trawler is a function of the crew size

The amount if prawn caught per week on a trawler is a function of the crew size assigned to operate the boat. Based on past data, the following production schedule was developed:

Crew Size Amount of prawn caught per week (Number of worker) (Hundreds of LBS) 2 3 3 6 4 11 5 19 6 24 7 28 8 31 9 33 10 34 11 34 12 33 a.) Over what ranges of workers are there (i) increasing, (ii) constant, (iii) decreasing and (iv) negative returns? b.) How large a crew should be used if the trawler owner is interested in maximizing the total amount of prawn caught?

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