Question 9 is 100 N.
Question 10 is No, the bike's motion is not changing so it could be at rest or moving at a constant velocity.
Question 11 is Be doubled.
Question 12 is Ella is correct.
Hope i helped.
If the velocity is constant then the acceleration of the object is zero.

Thus when we apply the equation
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It remains
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or equivalent
A. The particles are packed more tightly in materials with more density which causes the vibrations to bounce of the partials more rapidly which makes them go faster
Answer:
C. Neutral
Explanation:
Ions will combine in a way that the overall ionic compound will always be neutral.
Explanation:
The machine whose efficiency is 100% is known as perfect machine .This machine is not possible in real life because every machine is affected by the overcoming friction due to which is efficiency become less than hundred percent .