The speed of a: v = ST = 6m6s =1m/s; Speed of B: V' = s' t' = 9m12s = 0.75m/s; So a moves faster than b. Wrong choice.

B, according to the picture: the distance of A is 6m, and the distance of B is 9m, so the distance of A is smaller than that of B. The choice is correct.

C, A and B are exactly the same, and they are all placed on a horizontal plane. Both parties have the same pressure on the horizontal plane, the same roughness of the contact surface and the same friction force. The options are correct.

D. According to the image, both Party A and Party B move in a straight line at a uniform speed, and the resultant force on both parties is zero. Wrong choice.

So choose BC.