Inbreeding for five generations led to production of homozygous transgenic mice.However, these homozygous males or females were infertile. Which of the following approaches is most preferable and economical to obtain heterozygous transgenic animals continuously ?

Which of the following is the most appropriate choice as transgenic animal due to its short generation time?

In a cross between plants with purple flowers and plants with white flowers, the offspring of F_1 generation all had white flowers. When the F_1 generation was self-crossed, it was observed in the F_2 generation that out of 100, 75 flowers were white. Make a cross and answer the following questions: In a monohybrid cross between two heterozygous individuals, percentage of pure homozygous individuals obtained in F_1 generation is?