A function has a property such as "one input must be mapped to exactly one output." An input is the x-value, and the output is, generally, the y-value. In this set of points above, the input 3 maps to 4 <em>and </em>12, and therefore is not a function.
Answer: the answer is indeed (4,8)
Step-by-step explanation:
I think it is $0.27 because 15% of 1.80 is 0.27