According to the given data we have the following:
j is parallel to k
angle line of k=120°
Therefore, in order to calculate the measure of the missing angle we would calculate it by using the property of lineal pairs:
∠1 + ∠2=180°
120°+∠2=180°
∠2=180°-120°
∠2=60°
Therefore, the measure of the missing angle would be 60°
