A circle is drawn by touching all sides of the given square, a second square is drawn inside the circle such that the four corners of the square lies on circumference of a circle and a circle is drawn inside the second square in the same way and this process continues indefinitely. If the side of the first square is 2 cm, then the area of the fourth square in that process is ___ .
The circumference of a circle is 100 cm. The side of a square inscribed in the circle is: