Answer:
58.27 N
Explanation:
the data we have is:
mass: 
coefficient of friction: 
and we also know the acceleration of gravity is 
We need to do an analysis of horizontal and vertical forces acting on the object:
-------
Vertically the forces acting on the object:
- Normal force
(acting up from the object)
- weight:
(acting down from)
so the sum of forces in the vertical axis "y" are:

from Newton's second Law we know that
, so:

and since the object is not accelerating in the vertical direction (the movement is only horizontal)
, and:

-----------
now let's analyze the horizontal forces
- frictional force:
and since
--> 
- force to move the object:

and the two forces just mentioned must be opposite, thus the sum of forces in the "x" axis is:

and we are told that the crate moves at a steady speed, thus there is no acceleration: 
and we get:

substituting known values:

I think the answer is B but the problem in this part is that the South American plate has moved over time. You see the difference?
The sentence can be completed as follows:
"<span>The wavelength range of colors visible to humans ranges from 350 nm to 750 nm. light that most of us perceive as red is at 750 nm."
In fact, each different color is associated to a different sub-range of this range of wavelengths. Approximately, they are:
- violet: 350-450 nm
- blue: 450-495 nm
- green: 495-570 nm
- yellow: 570-590 nm
- orange: 590-620 nm
- red: 620-750 nm</span>
Answer:
<h3>According to our principle, when an object is slowing down, the acceleration is in the opposite direction as the velocity. Thus, this object has a negative acceleration. In Example D,<u> the object is moving in the negative direction</u> (i.e., has a negative velocity) and is speeding up.</h3>
Explanation:
So it would be decreasing if its moving towards the negative!
Answer:
Acceleration equals the change in velocity divided by time.
Explanation: