What is the average speed of the eight dump trucks after the first four hours?
Speed depends on what road conditions, as well as the condition of the car, the level of the driver and so on, so your question is not good to answer
In general, with an average speed of 30 kilometers per hour by, no-load can be calculated by 50, volume loading time, optic groove gauge, generally 35 minutes with a car, a truck to minutes, doing an hour to run twice. If you use the benefits of accounting, do not forget to repair the time, the domestic car attendance rate can be 25 days, a month is good.
Depends on the road conditions, but also depends on the specific configuration of this model.