If Heidi only gets paid when she is talking to clients, she will be working
... 9 × (40 min/60 (min/h)) = 6 h
per day.
Her $2.00 difference in pay per hour will result in a difference in pay per day of
... $2.00/h × 6 h/day = $12/day
Company B will pay Heidi $12 more for a day's work.