Four friends, Art, Roger, Paul, and Trisha, bake cookies, and all cookies have the same thickness. The shapes of the cookies differ, as shown. Each friend uses the same amount of dough.

• Art's cookies are trapezoids.

• Roger's cookies are rectangles.

• Paul's cookies are parallelograms.

• Trisha's cookies are triangles.

If Roger makes exactly 20 cookies from one batch of dough, how many cookies does Art make from the same amount of dough?