Question : In a $\triangle \mathrm{ABC}$, the bisectors of $\angle \mathrm{B}$ and $\angle \mathrm{C}$ meet at $\mathrm{O}$. If $\angle \mathrm{BOC}=142^{\circ}$, then the measure of $\angle \mathrm{A}$ is:

Option 1: $52^\circ$

Option 2: $68^\circ$

Option 3: $104^\circ$

Option 4: $116^\circ$

Question : ABCD is a cyclic quadrilateral such that AB is the diameter of the circle circumscribing it and $\angle $ADC = 118°. What is the measure of $\angle$BAC?

Option 1: 28°

Option 2: 45°

Option 3: 32°

Option 4: 30°

Question : ABCD is a cyclic quadrilateral such that AB is the diameter of the circle circumscribing it and $\angle A D C=148^{\circ}$. What is the measure of the $\angle BAC$?

Option 1: $32^{\circ}$

Option 2: $45^{\circ}$

Option 3: $58^{\circ}$

Option 4: $60^{\circ}$

Question : PA and PB are two tangents from a point P outside the circle with centre O. If A and B are points on the circle such that $\angle \mathrm{APB}=142^{\circ}$, then $\angle \mathrm{OAB}$ is equal to:

Option 1: 31°

Option 2: 58°

Option 3: 71°

Option 4: 64°

Question : PA and PB are two tangents from a point P outside the circle with centre O. If A and B are points on the circle such that $\angle \mathrm{APB}=128^{\circ}$, then $\angle \mathrm{OAB}$ is equal to:

Option 1: 72°

Option 2: 52°

Option 3: 38°

Option 4: 64°