geometry help?

1: http://i7.tinypic.com/6okhwkp.gif

Which theorem is used to prove the above statement?

If two angles are equal, their supplements are equal.

If two angles are equal, their compliments are equal.

If two straight lines intersect, then the opposite angles formed are equal in pairs.

2: angleAOC and angleBOD are right angles.

OB is the bisector of angleAOC.

OC is the bisector of angleBOD.

Which theorem is used to prove that angleAOB = angleCOD?

If two angles are equal, their supplements are equal.

If two angles are equal, their compliments are equal.

If two straight lines intersect, then the opposite angles formed are equal in pairs.

3: An angle PQR is bisected by the line QT, which is extended beyond Q to any point S. Prove that anglePQS = angleRQS.

Which theorem is used?

If two angles are equal, their supplements are equal.

If two angles are equal, their compliments are equal.

If two straight lines intersect, then the opposite angles formed are equal in pairs.

4: http://i7.tinypic.com/89r8x20.gif

Prove that angleULC = angle PLM.

Which theorem is used?

If two angles are equal, their supplements are equal.

If two angles are equal, their compliments are equal.

If two straight lines intersect, then the opposite angles formed are equal in pairs.