A is NOT a function because for some values of x you get more than one y value. For example if x=2 you get 2 values for y.
b is a function because for each x you get ONLY one y
Answer:30
Step-by-step explanation:
The answers is the last one
If x is the amount of time Gillian takes,
1/10 - 1/x = 1/25
Therefore, the answer is A
