Answer:
The energy is 
(a) is correct option
Explanation:
Given that,
Energy = 4480 j
Weight of nitrogen = 20 g
Boil temperature = 77 K
Pressure = 1 atm
We need to calculate the internal energy
Using first law of thermodynamics


Put the value into the formula



We need to calculate the number of molecules in 20 g N₂
Using formula of number of molecules

Put the value into the formula


We need to calculate the energy
Using formula of energy

Put the value into the formula


Hence, The energy is 
Answer:
- The impulse exerted by the ball is 7.2 kg.m/s
- The average force exerted on the ball by the bat is 600 N.
Explanation:
Given;
mass of the baseball, m = 0.144 kg
velocity of the baseball, v₁ = 20 m/s
velocity of the batter, v₂ = -30 m/s (opposite direction to the ball's speed)
The impulse exerted by the ball is calculated as follows;
J = ΔP = mv₁ - mv₂
ΔP = m(v₁ - v₂)
ΔP = 0.144 [20 - (-30)]
ΔP = 0.144 ( 20 + 30 )
ΔP = 0.144 (50)
ΔP = 7.2 kg.m/s
The average force exerted on the ball by the bat is calculated as;

Answer:
Going from earth to the sun a probe would encounter the next layers in order:
- Corona
- Transition Region
- Chromosphere
- Photosphere
- Convection Zone
- Radiative Zone
- Core
A brief description of them:
Corona is the outermost layer and it cannot be seen with the naked eye, is starts at about 2100 km from the surface of the sun and it has no limit defined.
Transition Region is between the corona and the chromosphere, it has an extension of about 100km
The chromosphere is between 400 km from the surface of the sun to 2100 km. In this layer the further you get away from the sun it gets hotter.
The photosphere is the surface of the sun, the part that we can see, and extends from the surface to 400km.
The convection zone is where convection happens, hot gas rises, cools and rises again.
Radiative Zone is where the photons try to rise to move to higher layers.
The core of the Sun is where nuclear fusion occurs due to the very high temperatures.
Water<span> can </span>dissolve salt<span> because the positive part of </span>water<span> molecules attracts the negative chloride ions and the negative part of </span>water<span> molecules attracts the positive sodium ions. The amount of a substance that can </span>dissolve<span> in a liquid (at a particular temperature) is called the solubility of the substance. So the solute is the salt and the solvent is the water. I believe that is correct.</span>
False ...................