Answer:
There are 2500000 milligrams in 2.5 kg
Explanation:
Since, density is the amount of mass present in per unit volume.
Mathematically, Density = 
As density is directly proportional to mass of a substance. So, more is the density of a substance more will be its mass. And, when more is the mass of a substance then it is likely to sink at the bottom.
Here, it is given that density of oxygen is more than the density of nitrogen. Therefore, balloons filled with oxygen will sink in the air.
On the other hand, balloons filled with nitrogen will rise in the air.
the answer is going to be 4.5
The correct answer is D. melting the solid.
Answer:
The absorption and strength of the H-beta lines change with the temperature of the stellar surface, and because of this, one can find the temperature of the star from their absorption lines and strength. To better comprehend, let us look into the concept of the atom's atomic structure.
Atoms possess distinct energy levels and these levels of energy are constant, that is, the temperature has no influence on it. However, temperature possesses an influence on the electron numbers found within these levels of energy. Therefore, to generate an absorption line of hydrogen in the electromagnetic spectrum's visible band, the electrons are required to be present in the second energy level, that is when it captivates a photon.
Therefore, after captivating the photons the electrons jump from level 2 to level 4, which shows that there is an increase in the stellar surface temperature and at the same time one can witness a decline in the strength of the H-beta lines. In case, if the temperature of the surface increases too much, then one will witness no attachment of electron with the hydrogen atom and thus no H lines, and if the temperature of the surface becomes too low, then the electrons will stay in the ground state and no formation of H lines will take place in that condition too.
Hence, to generate a very robust H line, after captivating photons the majority of the electrons are required to stay in the second energy level.
