The word for people who study fossils are paleontologists and they may use paint brushes to clean fossils for soft sedimentaries.
If it displays the dominant genotype, we can assume that this plant would have a heterozygous (hybrid) genotype, i.e.
With a purebred recessive plant, the geneotypes would be 50% Bb and 50% bb.
With a purebred dominant plant, the genetpyes would be 50% BB and 50% Bb.
With a <span>heterozygous (hybrid) plant, the genotypes would be 25% BB, 50% Bb and 25% bb.</span>
There is one extra 21 comosome which is why it is down sydrome.