What is the value represented by the letter a on the box plot of data? {5, 20, 40, 50, 50, 85} enter your answer in the box.

sample answer: you can determine whether each element of the domain is paired with exactly one element of the range. for example, if given a graph, you could use the vertical line test; if a vertical line intersects the graph more than once, then the relation that the graph represents is not a function.