It takes 6 beavers 10 hours to build a certain dam, working at a uniform rate. If six beavers start to build the same dam at noon, and one beaver per hour is added beginning at 6:00 PM, at what time will the dam be complete?
A) 7:40 PM
B) 8:00 PM
C) 8:20 PM
D) 8:40 PM
E) 9:00 PM
A) 7:40 PM
B) 8:00 PM
C) 8:20 PM
D) 8:40 PM
E) 9:00 PM












