Different data sources provide information about a road segment of length 10 km (0 ? x ? 10 km) indicating a road block caused by an accident: (i) At 4.00 p.m., a floating car enters the area and crosses it at 120 km/h. (ii) At 4.19 p.m., another floating car, driving at the same speed, has to stop at the end of a traffic jam at x = 5 km. (iii) Two stationary detectors at x = 4 and 8 km measure the traffic flow (but not the speed). The detector at x = 4 km reports a flow of zero between 4.25 and 4.58 p.m. The detector at x = 8 km reports zero flow between 4.14 and 4.51 p.m. (iv) At 4.40 p.m., a driver reports (via cell phone) that he has been stuck in a traffic jam at x = 5 km for a few minutes already. (v) At 4.30 p.m., another caller, driving on the opposite lane, reports an empty road at x = 7km. Determine the location and time of the accident, assuming an immediate and total roadblock causing a traffic jam that propagates upstream with constant velocity. Also, determine the propagation velocity

Different data sources provide information about a road segment of length 10 km (0 s x s 10 km) indicating a road block caused by an accident: (i) At 4.00 p.m., a floating car enters the area and crosses it at 120 km/h. (ii) At 4.19 p.m., another floating car, driving at the same speed, has to stop at the end of a traffic jam at x = 5 km. (iii) Two stationary detectors at x = 4 and 8 km measure the traffic flow (but not the speed). The detector at x = 4 km reports a flow of zero between 4.25 and 4.58 pm. The detector at x = 8 km reports zero flow between 4.14 and 4.51 pm. (iv) At 4.40 p.m., a driver reports (via cell phone) that he has been stuck in a traffic jam at x = 5 km for a few minutes already. (v) At 4.30 p.m., another caller, driving on the opposite lane, reports an empty road at x = 7km. Determine the location and time of the accident, assuming an immediate and total roadblock causing a traffic jam that propagates upstream with constant velocity. Also, determine the propagation velocity