Using proportions, it is found that the number of islands that each member will have to visit is given by:
c. 19 islands.
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
In this problem, there are 684 islands, and 36 members, hence the number of islands per member is given by:
n = 684/36 = 19.
Which means that option c is correct.
More can be learned about proportions at https://brainly.com/question/24372153
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