When recyclable materials are sent to a recycling plant, they are often not sorted in any particular way. Plastic materials might be mixed in with paper, iron, aluminum, and glass materials. Image courtesy of the U. S. EPA Which of the following is a way that recycling plants separate iron materials from other materials without applying a contact force to them? A. by applying a magnetic force to the recycled materials B. by sorting the materials by hand C. by sorting the materials with a robotic arm D. by applying an impact force to the recycled materials