Concept:The horizontal component of a force is found using the cosine of the angle between the force and the horizontal.Explanation:The formula for the horizontal component is Fx=Fcosθ.Here, applied force F=150N and θ=60∘.So, Fx=150cos60∘.Since cos60∘=0.5, we get Fx=150×0.5=75N.Answer:The horizontal component of the applied force is 75N, which is option B.