Answer:
b
dissolving is a chemical change
<span> In DNA, </span>guanine<span> is paired with cytosine. The </span>guanine<span> nucleoside is called </span>guano sine<span>.
i hope this helps!:D</span>
They come from the atmosphere, since plants use carbon dioxide to produce carbohydrates :)
Salinity and density share a positive relationship. As density increases, the amount of salts in the water—also known as salinity, increases. Various events can contribute to change in the density of seawater. Salinity can decrease from the melting of polar ice or increase from the freezing of polar ice.