22. The U.S. population in selected years between 1815 and 1965 is listed in the table below. Determine a quadratic equation in the form

, where t is the number of years after 1800 and P is the population in millions, that best fits the data. Use the equation to estimate the population in 1915 (the population was 98.8 millions). Make a plot of the population versus the year that shows the data points and the equation.