Elston attaches a spring scale to a box and pulls it across the floor. Hey, then place is a book in the box and pulls it in the same distance with the same effort. How does the force change after the book is placed in the box?A. It will decrease.B. It could increase or decrease, depending on the weight of the box.C. It could increase or decrease, depending on the weight of the book.D. It will increase.
