Use the information below to answer questions 4 through 10. Jenny runs a birdhouse manufacturing company. The number of birdhouses she can make with each number of laborers is shown in the table below. Labor Birdhouses 0 0 1 6 2 11 3 15 4 18 5 20 6 21 If birdhouses sell for $20 each when Jenny produces 19 or fewer and $18 each when Jenny produces 20 or more, how many workers will she hire if she pays wages of $40 per day