Jackson Dance Studio Has Had the Following Number of People

Jackson Dance Studio has had the following number of people signing up for dance lessons over the past three years. Calculate the anticipated demand for lessons in March, April, and May next year, given the seasonality of demand and a trend of Ft = 100 + 15t.
$$\begin{array} { | c | c | c | c | c | c | } \hline & \text { Year 1 } & & \text { Year 2 } & & \text { Year 3 } \\\hline \text { January } & 20 & \text { January } & 28 & \text { January } & 40 \\\hline \text { February } & 106 & \text { February } & 115 & \text { February } & 122 \\\hline \text { March } & 50 & \text { March } & 62 & \text { March } & 77 \\\hline \text { April } & 100 & \text { April } & 110 & \text { April } & 123 \\\hline \text { May } & 107 & \text { May } & 122 & \text { May } & 135 \\\hline\end{array}$$