6) An air plane is flying at a constant speed of 500.0 km/h. It executes a slow turn that changes its direction of travel from north through east, to south. If the turn takes 40.0 sec, the air plane's average acceleration is? 12)A passenger on a bus, walks toward the back of the bus at 3.0 km/h relative to the bus, while the bus travels south at 15 km/h relative to the road. The passenger's velocity relative to the road is ? 13) Car A is travelling north at 50 km/h relative to the road while directly behind it car B is travelling south at 30 km/h relative to the road. The velocity of car B relative to car A is ? 14)Two cars approach an intersection at right angles. Car A is travelling with a velocity of 30 km/h east relative to the road. Car B is travelling with a velocity of 30 km/h north relative to the road. What is the velocity of car B relative to car A