Q$5.$ The values of $x$ represents the number of year after the startup company is establish$v$ represents the yearly profit in hundred thousands that is made at the given year.

$\backslash$table$[[x,1,2,5,6,7],[y,2,2\mathrm{.}5,3\mathrm{.}5,3,3\mathrm{.}25]]$

Find the straight line that provides the best least$-$squares fit to the following data.