Greg made pudding every weekend. The more times he made pudding, the more practice he gained. The time he took to make the same amount of pudding every week decreased with practice. The function below shows the number of hours f(x) Greg took to make pudding after he had made it x times: f(x) = 2(0.8)x

Which graph best represents the function?

graph of an increasing exponential function going through eight tenths on the y axis
graph of a decreasing exponential function going through one on the y axis
graph of an increasing exponential function going through one on the y axis
graph of a decreasing exponential function going through two on the y axis