So we want to know what is the velocity of the private plane that is traveling east with velocity ve=150 mph and if the wind is blowing west with velocity vw=50 mph. So the overall velocity is v=sqrt(ve^2 + vw^2). Now we input the numbers: v=sqrt(150^2 + 50^2)=sqrt(22500+2500=sqrt(25000)=158.11 mph. So the correct answer is B. 158 mph.
