Mathematics

It takes a kayaker 36 minutes to paddle the first part of a trip and 1 hour and 40 minutes to paddle the second part of the trip. The kayaker's average speed on the first part of this trip was 2 miles per hour faster than on the second part of the trip. If the distance of the trip was a total of 8 miles, what was the kayaker's average speed, in miles per hour, on the first part of the trip?

A.2.4
B.3
C.5
D.6.7

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