20 represents how many hours you can rent a truck for $516.
Step-by-step explanation:
Part A:
The table does not represent y as a function of x. In order for it to be a function, there has to be one input to be an output. For example, 16 has 2 output and 81 has 2 output. Therefore, it does not represent y as a function.
Part B:
f(x)=25x+16
f(20)=25(20)+16
f(20)=500+16
f(x)=516
20 represents how many hours you can rent a truck for $516.
