这题怎么解？---**Question Stem:** 求蓝色区域面积 如图所示，正方形内有半圆弧线、1/4圆弧线和对角线，求三线所围蓝色区域的面积 **Other Relevant Text:** 4 4 4 **Chart/Diagram Description:** * **Type:** Geometric diagram within a square. * **Main Elements:** * **Square:** A square shape forms the boundary. Its side length is labeled as 4 on the top, left, and bottom sides. * **Diagonal Line:** A straight line segment connecting the top-left corner to the bottom-right corner of the square. * **Quarter-circle Arc:** A curved line segment from the bottom-left corner to the top-right corner. It is an arc of a circle centered at the bottom-left corner, with a radius equal to the side length of the square (4). * **Semi-circle Arc:** A curved line segment from the left edge to the bottom edge. It is an arc of a semi-circle whose diameter lies along the bottom edge of the square. The center of this semi-circle is the midpoint of the bottom edge, and its radius is half the side length of the square (2). * **Blue Region:** A region in the upper-right portion of the square. It is bounded by the top edge of the square, the diagonal line, and the quarter-circle arc. This region is colored blue. * **Shaded Region:** A region in the lower-left portion of the square. It is bounded by the left edge of the square, the bottom edge of the square, and the semi-circle arc. This region is shaded with vertical lines. * **Relative Position:** The square is oriented with its sides horizontal and vertical. The diagonal runs from top-left to bottom-right. The quarter-circle arc curves from the bottom-left corner towards the top-right. The semi-circle arc curves upwards from the bottom edge. The blue region is enclosed between the top edge, the diagonal, and the quarter-circle arc. The shaded region is enclosed between the left edge, the bottom edge, and the semi-circle arc.