<u>Answer:</u>
The characteristic that is common to "all three groups of reptiles" is that they are all ectotherms.
<u>Explanation:</u>
- Almost all the reptiles are referred to as 'ectotherms' because they are all cold-blooded.
- They adjust their body temperature according to the temperature of the surrounding.
- Reptiles like snakes do not have claws or eyelids. Moreover, not all reptiles protect their eggs.
- The "sea turtles" lay eggs on the seashores and go back to the seas.
- Thus, the only common characteristic among all the reptiles is that they are all ectotherms.
The two main factors that affect density of ocean water are the temperature of the water and the salinity of the water.
Oceanography is is the study of the physical and biological aspects of the ocean, so my assumption is an oceanographer is a person who studies those things.
Answer:
Big cities, convenience.
Explanation:
In the most densely populated areas of Europe and Russia, there are cities which means that things will be close to people. Cities provide convenient for people, they are more populated.
