Task: Explanation
Input (English): 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 less friction with the ground. 
 Answer: Sara
Output (English): Friction is greater when objects have rougher surfaces or are heavier so they press together with greater force.