A new species of grass has been identified with two genes located 10 cm apart. gene a produces a hormone that causes stems to grow. gene b produces small seeds. both genes show complete dominance over their recessive forms. a pure-breeding plant with a long stem and large seeds is crossed with a pure-breeding plant with a short stem and small seeds. the f1 offspring are then crossed with each other to produce the f2 generation. what are the expected phenotypic ratios of the f2 generation?