Choose the correct answer and give justification for each.

From a point Q, the length of the tangent to a circle is 24 cm. and the distance of Q from the centre is 25 cm. The radius of the circle is

A. 7 cm

B. 12 cm

C. 15 cm

D. 24.5 cm

Prove that the tangents to a circle at the end points of a diameter are parallel.

Choose the correct answer and give justification for each.

The angle between a tangent to a circle and the radius drawn at the point of contact is

A. 60^o

B. 30^o

C. 45^o

D. 90^o

Choose the correct answer and give justification for each.

If AP and AQ are the two tangents a circle with centre O so that ∠POQ = 110°, then ∠PAQ is equal to

A. 60^o

B. 70^o

C. 80^o

D. 90^o

Choose the correct answer and give justification for each.

If tangents PA and PB from a point P to a circle with centre O are inclined to each other at angle of 80^o, then ∠POA is equal to

A. 50^o

B. 60^o

C. 70^o

D. 80^o