B, C along the 400-meter circular track for 800 meters race, running a lap when the A, B and Bi Jia

If the speed of their respective running remained unchanged, then the When B reaches the finish line, in front of A in the C ()

A.85 m B.90 m m

C.100 meters D.105 needed Xiangjie Thank you! !

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Three speed remains unchanged, according to the shares ideas to solve this problem, a running 7 copies of A, B and ran 7 +1 = 8 copies, C = 6 were running 7-1.

B to reach the finish line to run the 800 meters, then ran 700 meters A, C and ran 600 meters

100 meters