D because Carbon and Oxygen form covalent compounds. I wasn't the greatest at chem., but I'm pretty sure this is correct :D let me know if I gave you the right answer.
The A horizon is a surface horizon that largely consists of minerals (sand<span>, </span>silt<span>, and </span>clay) and with appreciable amounts of organic matter. This horizon is predominantly the surface layer of many soils in grasslands and agricultural lands.<span>These </span>materials typically<span> accumulate through a process termed illuviation, wherein the </span>materials<span> gradually wash in from the overlying.</span>
The answer is C: The plum-pudding model
Follow Avogadro’s Number
1 mole = 6.02 x 10^23
So we can do it
4.77x10^25/6.02x10^23 = 79.2 mole