The shaded region below is bounded by the portion of the circle of radius $5$ and center $(0,0)$ that lies in the first quadrant, the portion of the circle with radius $\frac{5}{2}$ and center $(0,\frac{5}{2})$ that lies in the first quadrant, and the line segment from $(0,0)$ to $(5,0)$. What is the area of the shaded region?