1/4 Ao = Ao * ( 1/2)^(t/106)
t = 212
subtract 4.6 billion years
<span>d)</span>
Genetics is a term that refers to the study of genes and their roles in inheritance
Metallic bonds are forces that holds atoms together in a marlin substance
<span>PbO
Let's look at each of the 4 compounds and see what's needed.
PbO.
* Oxygen has a valance shell that's missing 2 electrons and wants to get those 2 elections. Lead donates them, so you have a Lead (II) ions. This is a correct choice.
PbCl4
* Chlorine wants to grab 1 electron to fill it's valance shell and Lead donates that election. However, there's 4 chlorine atoms and every one of them wants and electron, and lead is donating all 4 of the desired electrons making the Lead (IV) ion. So this is a bad choice.
Pb2O
* Oxygen still wants 2 electrons and gets them from the lead. But there's 2 lead atoms and each of them donates 1 election making for 2 Lead(I) ions. So this too is a bad choice.
Pb2S
* Sulfur is in the same column of the periodic table as oxygen and if this compound were to exist would have similar properties as Pb2O and would have Lead(I) ions. So this is a bad choice.</span>
Answer:
C
Explanation:
Plants help in carbon dioxode reduction so plants uses atmospheric carbon dioxide and water to produce sugars and oxygen.
HOPE ITS HOPEFUL.
