Question : A circle with centre O has a chord AB that is 20 cm in length. If the radius of the circle is 12 cm, then the area of triangle AOB is:

Option 1: $20 \sqrt{15}$ cm²

Option 2: $22 \sqrt{11}$ cm²

Option 3: $20 \sqrt{11}$ cm²

Option 4: $22 \sqrt{15}$ cm²

Question : PM and PN are two tangents of a circle from an external point P. M and N are points on the circle. If PM = y² – 9 and PN = 55, then what is the value of y?

Option 1: 64

Option 2: 17

Option 3: 8

Option 4: 12

Question : O is the centre of a circle with a diameter of 16 cm. Q is a point outside the circle and QS is tangent to the circle at point S. If OQ is =17 cm, what is the length (in cm) of the tangent QS?

Option 1: 15

Option 2: 12

Option 3: 18

Option 4: 10

Question : AB and BC are two chords of a circle with centre O. Both chords are on either side of the centre O. Point A and point C are connected to the centre O, such that $\angle B A O=36^{\circ}$ and $\angle B C O=48^{\circ}$. What is the degree measure of the angle subtended by the minor arc AC at the centre O?

Option 1: 136°

Option 2: 144°

Option 3: 120°

Option 4: 168°

Question : From a point P, two tangents PA and PB are drawn to a circle with centre O. If OP is equal to the diameter of the circle, then $\angle$APB is:

Option 1: 45°

Option 2: 90°

Option 3: 30°

Option 4: 60°