Amusic recording company has contracts with two bands. the cds of these bands are released in three countries, britain, canada, and australia. the total number of cds sold in each country is britain, 40,000; canada, 50,000; and australia, 30,000. the cost of advertising for both bands was $2 per cd in britain, $1.50 in canada, and $1 in australia. if matrix a = [2 1.5 1], what is matrix b if ab represents the total advertising cost (in dollars) for all three countries?