Question

1. list the sides in order from smallest to largest.

Explanation:

Step1: Calculate angle \(A\)

The sum of angles in a triangle is \(180^{\circ}\). So, \(A = 180^{\circ}-71^{\circ}-42^{\circ}=67^{\circ}\).

Step2: Recall the side - angle relationship

In a triangle, the larger the angle, the longer the side opposite it.

Step3: Compare the angles

We have \(42^{\circ}<67^{\circ}<71^{\circ}\), which are angles \(B\), \(A\), \(C\) respectively.

Step4: Determine the sides

The side opposite angle \(B\) is \(AC\), opposite \(A\) is \(BC\), and opposite \(C\) is \(AB\). So, \(AC < BC < AB\).

Answer:

\(AC\), \(BC\), \(AB\)