Need help friend request if you asian as in korean and so on cause I'm trying sotem new so don't ask

Will give brainliest if you answer question correct

What point is the projection of q on a) r b) s c) t

Steve wants to develop a way to find the total cost of any item including sales tax. the sales tax in his city is 6%. his friend jenna writes the expression x + 6x where x is the cost of the item. explain whether her expression is correct based on the situation.