A coefficient of determination is a measure of how well the graph of a regression fits the data set. The closer this coefficient is to 1, the better the fit.
The closest coefficient we have to 1 is 0.91, which is that of the exponential model. This means the exponential model is the best fit.
One liter is 1,000 ml. plus 299 ml. is 1,299 ml. plus the additonal 398 ml. is 1,697 ml. which is 722 ml. less than the total volume. (722 ml. of water can still be added.)
