Answer: D
Explanation: The Eukarya differ from the Archea and Bacteria in that their cells are eukaryotic, meaning they contain a membrane enclosed nucleus and other membrane enclosed organelles.
Food labels can tell someone how nutrient-dense a food is. It can show calories, fat, and others. Hope that helps.
First, we divide the number of atoms of silicon given in the problem above by Avogadro's number 6.6022 x10^23. This will give us the number of moles of silicon. Then, we multiply the number of moles by the molar mass of silicon.
number of moles = (3.6 x 10^20 atoms/6.022x10^23 atoms) = 5.97x10^-4 moles
Then, multiplying by the molar mass
(5.97x10^-4 moles)(28.0855 g/mol) = 0.017 grams
So half life is the time taken for a sample to decay to half its original mass, its a constant and applies to any original mass, it could be 5g or 1kg, it will take the same amount of time for the original mass to half. In this case the half life is 3 days.
After 3 days the sample will be at half its original mass, now 50g.
Now we can treat the 50g as if its a new sample. After another 3 days (6 days in total) there will be half of 50g left, = 25g.