Using the combination formula, it is found that Julia can take 15 combinations.
<h3>What is the combination formula?</h3> is the number of different combinations of x objects from a set of n elements, given by:
For this problem, 4 students are taken from a set of 6, hence the number of combinations is given as follows:
More can be learned about the combination formula at brainly.com/question/25821700
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