Hello, sorry this is a little late!
I believe the correct answer to your question would be option D, <span>electric charges have electric fields surrounding them to allow them to exert forces on other objects without touching them.
I just took this test, and can 100% confirm this is the proper answer.
Hope this helps, and have a great day! :)</span>
Answer:
Magnitude of the force is 2601.9 N
Explanation:
m = 450 kg
coefficient of static friction μs = 0.73
coefficient of kinetic friction is μk = 0.59
The force required to start crate moving is
.
but once crate starts moving the force of friction is reduced
.
Hence to keep crate moving at constant velocity we have to reduce the force pushing crate ie
.
Then the above pushing force will equal the frictional force due to kinetic friction and constant velocity is possible as forces are balanced.
Magnitude of the force

I remember c/d. That's not a problem. But if you want 'c', you'll have to give me 'd'.
Answer:
B) 18,000 feet MSL
Explanation:
There are three-dimensional parts in the navigation airspace in the world. The class E airspace is mostly used in the regions with coastal areas that are relatively populated. If we consider certain forms of exceptions, the class E airspace can move in the upward direction to few feet (i.e. 1200 ft). However, this doesn't include 18,000 feet MSL.