Question: 1. A wheel tractor-scraper whose weight on the driving wheels is 38,720 lb (17,563 kg) has a gross weight of 70,400 lb (31,933 kg). If the road surface is dry earth with a rolling resistance factor of 100 lb/ton (50 kg/t), what is the maximum grade the scraper could ascend?
2. What is a pull-scraper? What advantages does it have over conventional scrapers?
3. Write a computer program to calculate the number of pushers required to service a specified scraper fleet. Input should include scraper cycle time, method of push-loading, and whether single or tandem pushers will be used.