The Answer is D) equal hydrogen and hydroxide-ion concentration
Answer:
F = 51.3°
Explanation:
The component of weight parallel to the inclined plane must be responsible for the rolling back motion of the car. Hence, the force required to be applied by the child must also be equal to that component of weight:

where,
W = Weight of Wagon = 150 N
θ = Angle of Inclinition = 20°
Therefore,

<u>F = 51.3°</u>
Answer:
They do this because it covers the whole surface which they are cleaning. the cleaner all hold the same charge and repel from each other and cover the whole surface. They want to do this to make sure the item that they cleaning is clean.
Okay, I don't know if this question is supposed to be a trick question or not. The weight of the apple does not change as the plane travels up the atmosphere, but the MASS changes. Weight doesn't change no matter what environment you're in, but the mass changes in different environments. In this case, the weight is constant but the mass is decreasing as you go higher up.