Answer:
78
Step-by-step explanation:
∠A + ∠B + ∠C = 180 { Angle sum property of triangle}
42 + ∠B + 60 = 180
∠B + 102 = 180
∠B = 180 - 102 = 78
In similar triangles, corresponding angles are congruent.
∠S ≅ ∠B
∠S = 78°
Total miles:350+150=500
Total hours:4+3=7
Avg speed:500/7=71.429 mph
You can show it 4 ways by rotating the paper and if that is not an option, then the answer is 2.
