Donovan has offers for two sales jobs. Job A pays a base salary of $25,000 plus a 10% commission on sales. Job B pays a base salary of $30,000 plus 8% commission on sales. a. How much would Donovan have to sell for the salary from Job A to exceed the salary from Job B? b. If Donovan routinely sells more than $500,000 in merchandise, which job would result in a higher salary?