Please find the answers for the questions ---18. (This question is worth 16 points) In the Cartesian coordinate system xOy, two lines passing through point P(0,1) and perpendicular to each other intersect circle O: x^2 + y^2 = 4 at points A, B, and intersect circle M: (x-2)^2 + (y-1)^2 = 1 at points C, D. (1) If AB = (3/2)√7, find the length of CD. (2) If E is the midpoint of CD, find the range of the area of triangle ABE. **Chart/Diagram Description:** * **Type:** Geometric figure illustrating circles and lines in a Cartesian coordinate system. * **Main Elements:** * **Coordinate Axes:** x-axis and y-axis intersecting at the origin O. Arrows indicate positive directions. * **Origin:** Point O at the intersection of the axes, labeled O. * **Point P:** Labeled P on the y-axis, shown at y=1. (Coordinates P(0,1)). * **Circle O:** Centered at the origin O(0,0). Appears to pass through points A and B. Radius is 2 (from equation x^2+y^2=4). P is inside this circle. * **Circle M:** Centered at point M(2,1). Appears to pass through points C and D. Radius is 1 (from equation (x-2)^2+(y-1)^2=1). M is labeled M. P is outside this circle. * **Lines:** * One straight line passes through points B, P, A, and also through point O. This line intersects Circle O at A and B. * Another straight line passes through points C, P, E, D. This line intersects Circle M at C and D. * The two lines passing through P appear to be perpendicular to each other at P. * **Points of Intersection:** * A and B are on Circle O and the line passing through P. * C and D are on Circle M and the line passing through P (different from the line through A, B). * **Point E:** Labeled E, shown on the line passing through C, P, D. Mentioned as the midpoint of CD in the question. * **Labels:** O, P, A, B, M, C, D, E, x, y.