A plane travels in a straight line from position A to position B in 69 min , moving at an average speed of 420 km/h . In a car traveling from A to B, the driver finds that the trip is 600 km long by the route he is forced to take, which goes straight south for a certain distance and then straight west for a longer distance. At what angle south of west does the plane travel?

Consider a production line with five stations. station 1 can produce a unit in 9 minutes. station 2 can produce a unit in 10 minutes. station 3 has two identical machines, each of which can process a unit in 12 minutes (each unit only needs to be processed on one of the two machines. station 4 can produce a unit in 5 minutes. station 5 can produce a unit in 8 minutes. which station is the bottleneck station?