Navigation between three locations

A boat travels 18 km from \(A\) to \(B\) on a bearing of \(035^\circ\), then 24 km from \(B\) to \(C\) on a bearing of \(110^\circ\). All locations lie in the same horizontal plane. North lines are parallel.

The diagram is not drawn to scale.

1. Find \(\angle ABC\), explaining the bearing relationship used.[2]
2. Calculate the direct distance \(AC\).[3]
3. Use the sine rule to find \(\angle BCA\), then calculate the bearing of \(A\) from \(C\). Give the bearing to 1 decimal place.[4]
4. Explain why the obtuse angle with the same sine cannot be used for the angle at C.[1]