Answers

2014-03-04T22:41:56+05:30
AP = 3 {radius when perpendicular to chord bisects it }
QC = 4 {radius when perpendicular to chord bisects it }
Applying pythagoras theorem 
In OAP
OP=4
In OCQ
OQ=3 
OP=PQ+OQ
4=PQ+3
therefore PQ = 1 
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2014-03-05T00:10:09+05:30
In ΔCOQ
OQ=3
In ΔAOP
OP=4
OP=OQ+QP
4=3+QP
QP=4-3=1
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