it is assigned to deliver products to a destination with a distance of 40 km.The truck may arrive at the destination point at about 5 pm. The store is unable to do unloading right away. The unloading will take place the next day at 9 am. and complete at 10 am. Thus,for 24 hours, the truck is traveling for 2 hours , longing for 40 minutes, and the rest of the time is spent for waiting