27. Pilar obtained estimates for cleaning her furnace from 2 heating companies. Lehman Heating's estimate was $30 for a service call plus $22 per hour for cleaning the furnace. A-1 Heating's estimate was $35 for a service call plus $20 per hour for cleaning the furnace. If the estimates were the same in both the total amount and the number of hours for cleaning Pilar's furnace, how many hours for cleaning the furnace were reflected in the estimates?

B.

D.