A 62.5-kg crate rests on a level floor at a shipping dock. The coefficients of static and kinetic friction are 0.687 and 0.317, respectively. What horizontal pushing force is required to (a) just start the crate moving and (b) slide the crate across the dock at a constant speed

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Explanation:

h t t p s  : / / q u i  z l e t . c o m / e x p l a n a t i o n s / q u e s t i o n s / a - 6 0 0 - k g - c r a t e - r e s t s - o n - a - l e v e l - f l o o r - a t - a - s h i p p i n g - d o c k - t  h e - c o e f f i c i e n t s - o f - s t a t i c - a n d - k in e t i c - f r i c- 1 b b e 1 1 1 f - 8 e a 9 - 4 4 4 c - 8 5 d 2 - f a 2 e 3 0 d d f 0 b  9

Try it with out the spaces it does not let me with out the spaces. I think its easy to erase the spaces

temp rises, and expansion

d) physical means can be used to separate the components of air.