Question

please someone help me . those will answer correct , I will mark him/her as brainliest one .

Answer 1

4 cm
BQ = 11 -7= 4
BR = BQ

Answer 2

You must be knowing that tangents from exterior point are equal therefore PC=QC now since ARB is also a tangent to the circle therefore angle ORB=90°
Now QB = RB
as these are tangents from the exterior point
B as angle OQB =90° Hence QB=QC-BC=4cm
Therefore RB=4 cm