Hope you could understand.
If you have any query, feel free to ask.
Answer:
<h3>hope its help u.................</h3>
To find average atomic mass you multiply the mass of each isotope by its percentage, and then add the values up.
35 * 0.90 + 37 * 0.08 + 38 * 0.02 = 35.22
Average atomic mass closest to 35.22 amu.
The correct answer for this question would be option B. The common name of the group whose members are characterized by endoskeleton and a unique water vascular system are called the <span> Echinoderms. Examples of echinoderms are starfish, sea urchin, feather stars and sea cucumbers. Hope this is the answer that you are looking for.</span>
<span>Day and night are not exactly of equal length at the time of the March and September equinoxes. The dates on which day and night are each 12 hours occur a few days before and after the equinoxes.</span>
