A school teacher needs to distribute 21 pencils and 35 paint brushes into her students' art boxes. The sum is shown below. She wants to make sure that every student has the same number of pencils and the same number of paint brushes. She also wants to use all of the pencils and paint brushes.

Select the three correct statements, assuming each art box has the same number of pencils and the same number of paint brushes.

The teacher can make exactly 7 art boxes.
If the teacher makes 6 art boxes, there will be leftover pencils and paint brushes.
Each student will get 2 pencils and 4 paint brushes in the art box.
Each art box will contain 7 pencils and paint brushes.
The teacher can make exactly 8 art boxes.
Each student will get 3 pencils and 5 paint brushes in the art box.