Table Monthly Sales Temperature

March $20174,85055$

April $5,50059$

May $5,92062$

June $6,99072$

July $7,49085$

August $7,85089$

September $6,79084$

October $4,38071$

November $5,21052$

December $4,40042$

January $20182,93044$

February $2,48045$ After graduation, you take a position at Top$-$Slice, a well$-$known manufacturer of golf balls. One of your duties is to

forecast monthly demand for golf balls. Using the following data, you developed a regression model that expresses

monthly sales as a function of average temperature for the month:

Monthly sales $=-188\mathrm{.}4+88\mathrm{.}2($average temperature$)$

Click the icon to view the additional data.

a$.$ Show how the hat$(a)$ and hat$(b)$ values of $-188\mathrm{.}4$ and $88\mathrm{.}2$ were calculated.

Calculate the slope coefficient, hat$(b)($enter your responses as whole numbers$).$