If a star is moving towards you, how does it affect the wavelength of the light waves that reach you?

when a star is moving towards you: wavelength decreases
when a star is moving further away from you: wavelength increases

Agene pool: a) is the collection of all the alleles found in a single species b) is the collection of all the alleles found in a single population c) is the collection of all the chromosomes found in a single population d) is the collection of genes in a species that allow the individuals to swim