Please choose the correct answer to the question: 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?

Answer1: 20 km/h in the direction of bus A Answer2: 20 km/h in the direction of bus B Answer3: 30 km/h in the direction of bus A Answer4: 30 km/h in the direction of bus B

Answer format: answer1/answer2/answer3/answer4
Answer: answer1