B.
The cynobacteria were already there without the oxygen, so that rules out A, and a lot of prokaryotes were anaerobic, so that rules out C. Finally, Photosynthesis does not require oxygen. Instead, Oxygen is a waste product of it. Therefore, it cannot be D. So, we are only left with B
Hoped this helped :D
Answer:
Scientific Question: ... I will boil water and add a substance like salt to see if the boiling point increases.
Mass atomic of Ne=20.18 u
Therefore:
molar mass=20.18 g/1 mol
1 mole=6.022*10²³ particles (atoms or molecules)
Then: 6.022*10²³ atoms are contained in 20.18g
Now, We can solve this problem by the three rule.
6.022*10²³ atoms-------------------20.18 g
x------------------------------------------32 g
x=(6.022*10²³ atoms * 32 g)/20.18 g=9.55*10²³ atoms.
Answer: 9.55*10²³ Ne atoms are contained in 32 g of the element.
this is the formula and answer of this question
The liquid did not chemically bond after 3 days, therefor it is a mixture.
Hope this helps!
