About what percentage of all existing transgenic animals are mice?

After the safety of a vaccine is successfully tested in $.........$,it can be used in $.........$.

Consider the following statements about 'Rosie':
$I$. Rosie is the first transgenic cow.
$II$. Rosie produced human protein-enriched milk.
$III$. The milk contained the human $\alpha$-lactalbumin,and scientists believe that the milk from this cow could provide an alternative to human breast milk.
Which of the statements given above are correct?

The maximum number of existing transgenic animals is of which of the following?

With respect to understanding 'diseases', discuss the importance of transgenic animal models.

Transgenic organisms are produced by: