Answer:
A.compared
Explanation:
Fossils help figure out the time that organisms lived. If you know one of the fossils, it can be used as a reference for others around.
Which of the following is it though...?
Oxygen has an atomic number 8, because it has 8 protons and 8 electrons.
The first shell of an atom can hold up to 2 electrons but oxygen has 8 electrons, in that eight electrons 2 are in the first shell, so it has 6 more electrons left. The second shell can hold up to 8 electrons, oxygen has only 6 more electrons after the first shell is full, so it will have 6 electrons in the second shell
From this we know that oxygen has 2 shells so it is in period 2, and by counting from left to right, the sixth box in period 2 lies on group 16
Therefore Oxygen lies on group 16 and period 2
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Answer:
.
Explanation:
The average kinetic energy per molecule of a ideal gas is given by:

Now, we know that 
Before the absorption we have:
(1)
After the absorption,
(2)
If we want the ratio of v2/v1, let's divide the equation (2) by the equation (1)




Therefore the ratio will be 
I hope it helps you!