230 \ u (12+11) =10km.

10×12 =120km

11×10 =110 km

A car speed 120km, B car speed 1 10km.

6, 12 minutes = 1/5 hours

30× 1/5(40-30)= 0.6 hours

0.6×40=24 km

The distance between a and b is 24 kilometers.

7,300 ÷ 5/2 =120m

300/ 1/2 = 600 meters

(600+120) ÷ 2 = 360m

600-360 = 240m

The speed of A is 360 meters, and the speed of B is 240 meters.