Cats can have long tails (LL) or have no tail, which is called a bob tail cat (NN).  The intermediate tail length, medium, is a result of the heterozygous condition. Cross a long tail cat with a medium tail cat.  Give the genotype and phenotype percentages. 

clumped distribution, because you'de have all of the population gathered in a relatively small are.

it's the most common because it provides protection and a mate for reproduction

example: humans, seeweed, cattles, etc.

trachea, alveoli, lung capillaries, arteries

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint