Traveling in opposite directions, buses A and B are passing each other at the relative speed of 25 km/h, while a passenger on bus A walks toward the back of the bus at the speed of 5 km/h. What is the velocity of the passenger on bus A relative to bus B?
20 km/h in the direction of bus A 20 km/h in the direction of bus B 30 km/h in the direction of bus A 30 km/h in the direction of bus B