Lamarck's hypothesis of evolution was based on the theory of acquired inheritance.
The allele would be called codominant
When a dominant and recessive allele exist in an organism, only the dominant allele will be expressed. Dominant allele always mask the recessive because the gene code a protein while recessive gene doesn't. When both gene code a protein, they will be codominant and both gene will be expressed. The result could be a mixed effect. In this case, the purple is mixed color of red and blue.
Archaea means ancient, bacteria are, well, minuscule organisms that live everywhere, and eukarya are organisms with cells that have a nucleus as well as membrane-bound organelles... my best guess if it is planets you mean, then the answer would be archaea, if it is plants, like flowers or such, then it is eukarya.
I hope this helps!