Given the data shown, for time periods in months $(t)$ and demand $(y)$

$-$Does the data exhibit any trends? Draw and show your trend using Excel

Calculate a and $b$ for the linear trend equation and write the equation

$-$What are the forecasts for week $19-25?$ Show your work in Excel

Draw the trendline again with the forecast data using Excel.

Month wise Demand Data

$\backslash$table$[[$Period $($in months$),$Demand$],[1,405],[2,410],[3,420],[4,415],[5,412],[6,420],[7,424],[8,433],[9,438],[10,440],[11,446],[12,451],[13,455],[14,464],[15,466],[16,474],[17,476],[18,482]]$