Which of the following factors can affect a dumper's performance?

The performance of a dumper is influenced by several factors, which include both weather conditions and the type of materials being transported. Weather conditions can have a significant impact; for example, rain or snow may make surfaces slippery, reducing traction and affecting the dumper's ability to maneuver safely and efficiently. On the other hand, the type of materials being transported plays a crucial role; heavier materials may require different handling techniques and can cause strain on the dumper if not managed properly. Additionally, materials that are loose or wet can shift during transport, requiring more careful operation to maintain control and stability. Therefore, both these factors are vital to understanding and improving dumper performance, making the inclusion of both in the correct answer essential.