Yes they can
no the goldfish would it the tadpole
No. Shubunkins and Comets are about the same. A garden pond is the best place for all goldfish including the above.
Either a tank or pond of at least 30 gallons is a suitable environment for a goldfish.
Though this is not an EXACT estimate, Goldfish, if kept in a outdoor pond, will hibernate from November/December to February.
pond
Only fish like goldfish could live in your garden in a pond
A goldfish can live in an opaque glass tank as long as you keep up with necessary water changes. Like a small outside garden pond goldfish are only viewed from the top.
pond
yes
The goldfish will eat the mosquito's larvae before they can leave the pond and fly.
the common goldfish changes size depending on its home. if a small goldfish is kept in a little bowl it will not grow, however if it is kept in a large aquarium or pond it will grow much larger than its orginial size. therefore a gold fish can represent growth or the saying "a big fish in a little pond". but a koi fish which can be easily confused with a goldfish is completely different. the koi fish represents courage so look into that further if you're interested.
This is a literature question not a goldfish one.