dear friend, again pliz solve this question.
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Answer:
16. Uniform motion: straight line
Non uniform motion: curved line
18: two factor: nature of the surface either smooth or rough and coefficient of friction of the surface.
19. Momentum is defined as product of mass and velocity. It is a vector quantity.
Formula= p=mv
Unit=kilogram meters per second (kg⋅m/s) or Newton.second
(N.s)