The eighth grade math problem is one problem a day.

1. When they first met, the two cars traveled the distance from A to B;

From the first meeting to the second meeting, the two cars traveled twice the distance from A to B 。

So it took two hours to meet for the first time.

2. The first time we met, the location was 80 kilometers away from City A, that is, Car A traveled 80 kilometers.

Therefore, the speed of car A is 40 km/h.

3. The first meeting is 80 kilometers away from City A, and the second meeting is 40 kilometers away from City A. 。

That is, from the first meeting to the second meeting, the B car traveled 120 km.

Therefore, the speed of car B is 30 km/h.

In addition, it can be calculated that the distance between A and B is 140 km.