a
2) right bottom [tangents drawn to a circle from the same point are equal in length]
3) a
4) b
[Triangles AEC and DEB are similar triangles. So corresponding sides are proportional. So, AE/DE = CE/BE.]
5) c
6) a
7) c
8) b
9) a
10) c
11) d
12) a
13) d
14) a
15) b
16) c
17) c
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