Answer:D. Nerve cord, notochord, gut
<span>Irwin Rosenstock developed this model. His research was used to show why so few people undertake preventative measures for diseases and illnesses. This model shows that people tend to think that they are healthier than they might be, so there is no need for them to get screenings or other types of treatment.</span>
The answer to your question is A. <span>Near the poles as sea ice forms
Density means a closely compacted substance or liquid.
In the poles, it is very cold. Therefore, huge ice glaciers are formed from compacting water. Making the poles have the densest water found in the oceans.
Hope this helped. Have a great day!</span>
Answer:
To establish the age of a rock or a fossil, researchers use some type of clock to determine the date it was formed. Geologists commonly use radiometric dating methods, based on the natural radioactive decay of certain elements such as potassium and carbon, as reliable clocks to date ancient events.
Explanation: