The answer is Echinoderms.
According to the Embryological studies, the most ancient chordates were closely related to the ancestors of the echinoderms. Echinoderms are members of the group Phylum Echinodermata of marine animals. Some known echinoderms are starfish, and sea cucumbers.
Alternative ways of representing nucleic acid chains, in this case a single strand of DNA containing only three bases: cytosine (C), adenine (A), and guanine (G). ... This structural difference is critical to the different functions of the two types of nucleic acids.
Answer:
Electrons Can Donate - 0
Electrons Can Receive- 2
Valence - 2
Explanation:
The electronic configuration of oxygen is 
. Thus in the p-orbital there is deficiency of two electrons. Hence, it can receive/share electron but it cannot donate electrons. This makes oxygen as a good electron acceptor. Since there is a deficiency of two electrons in the outermost shell of oxygen, the valence of oxygen in thus -2
Answer:
Yes.
Explanation:
If the graph line comes lowers from 1999 to 2013 so it means that steps taken by the EPA and the factories were effective in reducing air pollution. The steps taken by the EPA and the factories were effective in reducing air pollution occurs from two pollutants i. e nitrogen oxides (NOx) and sulfur dioxide (SO2) if they install chimneys which collect these gases and reduce pollution. if the factories uses coal having less concentration of sulphur so less air pollution occurs.
