Teacher:In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.
Teacher: Now, understand the problem? Solve this instance: Question: Karen is studying friction in school. She wonders, of her two twin friends Sara and Samantha, which is causing more friction with the floor. They have on different shoes. Sara is wearing smooth soled tap shoes, while Samantha is wearing much rougher soled work boots. Assuming their weight is the same and all other factors are constant, _____ is creating more friction with the ground. 
 Answer: Samantha
Student:
Friction is greater when objects have rougher surfaces or are heavier so they press together with greater force.