Use the following information to answer questions on this page.

Colgate launched the "Smile for Good" toothpaste line, made with $99\mathrm{.}7\%$ ingredients from

natural sources. To increase its awareness and penetration into the market, Colgate ran

massive in$-$store promotions and education campaigns about its ingredients. For $40$ weeks

of sales and various in$-$store promotions, and smart retail data that tracks customer

shopping interaction $($e$.$g$.,$ coupon usage$),$ you have observed the sales $($in the number of

units sold$)$ of the "Smile for Good" line $($i$.$e$.,$ focal brand$)$ sales at Woolworth. Each week, you

keep track of the following three promotion activities:

a$.$ Was the focal brand featured in the in$-$store flyer? Related variable: Feature

b$.$ Was a coupon for the focal brand given to each customer? Related variable:

Coupon

c$.$ Was a shelf price reduction, i$.$e$.,$ sales promotions $($none$,10,$ or $25$ cents off$)$

given? Related dummy variables: PriceRed$1(10$ cents reduction from the regular

price$)$ and PriceRed$2(25$ cents reduction from the regular price$).$

Conducting a regression using Sales as the dependent variable and Feature, Coupon,

PriceRed $1$ and PriceRed $2$ as the independent variables, you get the following output $($see

below$).$