Well the US doesn't naturally have a lot of fossil fuels so we rely on other countries who do have fossil fuels. So if we aren't that friendly with Saudia Arabia (they have a bunch of oil) then they can hike up the prices or cut us off from their oil supply completely which would cripple the US severly. So with that being said, we NEED other countries, and the big question is when will they not NEED us. At any point in which they feel that they don't need us they can just cut us off, which would be bad.
Hope that helps :)
<span>1. Kuiper Belt object is made of frozen is made of frozen gas, ice, and dust that orbits in the outermost reaches of the solar system. Kuiper belt is a region which is filled with icy gaz bodies. Its structure is almost the same as the asteroid belt between Mars and Jupiter. Pluto, Makemake, Haumea are the officially recognized planets which are located in this region.
2. In my opinion, the most suitable option is: 3) The planets formed at the center of a collapsing spinning cloud of gas and dust. According to theory of solar system formation, the solar system appeared after a supernova (star explosion). A cloud of gas and dust was collapsed, and it caused a formation of a solar nebula.
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Explanation:
The position vector r:

The velocity vector v:

The acceleration vector a:



Answer:
The maximum safe depth in salt water is 3758.2 m.
Explanation:
Given that,
Diameter = 20 cm
Radius = 10 cm
Thickness = 9.0 cm
Force 
Inside pressure = 1.0 atm
We need to calculate the area
Using formula of area

Put the value into the formula


We need to calculate the pressure
Using formula of pressure

Put the value into the formula



We need to calculate the maximum depth
Using equation of pressure


Put the value into the formula


Hence, The maximum safe depth in salt water is 3758.2 m.
Answer: The density of this piece of jewelry is 
Explanation:
To calculate the density, we use the equation:

Mass of piece of jewellery = 130.8 g
Density of piece of jewellery = ?
Volume of piece of jewellery =( 62.4-47.7 ) ml = 14.7 ml =

Putting values in above equation, we get:

Thus density of this piece of jewelry is 