Solid sodium hydroxide (NaOH) is added to a beaker containing distilled water. Which statement below BEST describes the changes that occur after the addition of NaOH? A. The hydroxyl ion concentration decreases and the pH increases.
B. The hydroxyl ion concentration increases and the pH decreases.
C. The hydronium ion concentration decreases and the pH increases.
D. The hydronium ion concentration increases and the pH decreases.

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.