A company sells fast food including mineral water, milk tea, dumplings, and cold meat sandwiches at a fair. There are 4 places where the fair takes place including 4 areas: north, south, east, and west. The number of food units mentioned above sold in one day of the fair and the selling price of each unit of NS are given in the table below. a, create a matrix model to calculate the revenue of each region north, south, east, and west and the total revenue of this company. b calculate the revenue of each region north, south, east, west, and the total revenue of all 4 products of the company on this day.
