A music recording company has contracts with two bands. it released a new cd from each band in three countries: britain, canada, and australia. the company sold a total of 40,000 cds in britain, 50,000 in canada, and 30,000 in australia. the advertising cost was $2 per cd in britain, $1.50 in canada, and $1 in australia. if matrix a = [2 1.5 1] and ab represents the total advertising cost (in dollars) for all three countries, the order of matrix b is___, and the order of matrix ab is___. the total advertising cost for all three countries is $___.