D

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B C

A E In the figure, points A, B, C, D, and E lie on a line. A is on both circles, B is the center of the smaller circle, C is the center of the larger circle, D is on the smaller circle, and E is on the larger circle. What is the area of the region inside the larger circle and outside the smaller circle?

(1) AB = 3 and BC =2

(2) CD =1 and DE = 4

the key is A.

but my question is: if cd= 1 , de= 4, then R for Big Circle is CE=5=CA, then r for small circle should be (ca+cd)/2=3=ab,

then the area should be (25pai-9pai)=16pai.

so why the key is not D?

Thx