Detailed step-by-step solution:
Let’s consider all the inputs of each relationship given above.
We know:
1.If all the inputs are not engaged in a relation from \(x\) to \(y,\) then the relation does not qualify as a function.
2. Every input should be related to exactly one output. If that’s not the case, then the relation will not qualify as a function.
Cyclist 1:
Here, \(20\) minutes were taken to cover \(3\) miles and \(4\) miles in separate intervals, i.e., for \(20\) as input, there are two outputs, \(3\) and \(4.\)
It indicates that for a single input, there exists more than one output.
So this relation cannot be considered as a function.
Cyclist 2:
Here, the input-output combinations are: \((20, 3.5), (30, 5), (40, 6), (50, 7), (60, 8)\)
That is, for each value in the input, there exists a unique output.
So this relation will be considered as a function.
So, option D is the correct answer.