~~9. genetically speaking, why is it important not to mate with a close relative

While linebreeding is less likely to cause problems in the first generation than does inbreeding, over time, linebreeding can reduce the genetic diversity of a population and cause problems related to a too-small gene pool that may include an increased prevalence of genetic disorders and inbreeding depression

Explanation:

They can, do, and have done so!  

The reason it's bad to do it for several generations, is because there is a lack of genetic variety, and genetic diseases eventually begin to appear, such as hemophilia, deformities, etc.  

The British Royalty was an example of this, several hundred years ago!

Explanation:

plato users

given bodies of water

pacific / arctic / indian / southern

[ a ] the caribbean sea

[ b ] the northern ocean

[ c ] the atlantic ocean

[ d ] the barents sea

with this being the given answers

b ti isnfornopgnoernfrof