#### Answer

(a) See graph.
(b) $y = 6.1036x^2 - 9.2774x + 16.433$
(c) $652.92$
(d) Yes, see explanations.

#### Work Step by Step

(a) We can make a scatterplot of the data as shown in the figure.
(b) A regression quadratic $y = 6.1036x^2 - 9.2774x + 16.433$ can be found and superimposed on the scatterplot as shown.
(c) After 11 hours, we have $y = 6.1036(11)^2 - 9.2774(11) + 16.433\approx652.92$
(d) Because the quadratic curve showed a good fit to the data set, it is expected that it would provide a good estimate of the biomass after 18 hours. However, cell growths usually follow an exponential model, thus using an exponential function for the regression will give more reliable results.