c$.$ Using simple linear regression, calculate the trend line for the historical data. Say the $x$ axis is April $=1,$ May $=2,$ and so on$,$ while the $Y$ axis is demand.

Note: Round your intercept value to the nearest whole number and slope value to $2$ decimal places.

$Y=$

d$.$ Calculate a forecast for October using your regression formula.

Note: Round your answer to $2$ decimal places.

Forecast for October