They're like Pokémons; first they gotta train and level up, then they evolve and grow.

It's quicker if you grow them with the electric eels.

It depends on how well you feed it.

Depends how powerful the explosion is so I'm not sure but It takes days to start a nuclear powerplant so they keep it on all the time <3

Exactly two half-lives.

Depends. You have to water them with heavy water.

It depends on the species of power plant. If it's a uranium species, it'll be 1.4 billion years (because 2* the half-life of 700 million years makes a full life).

Let me check my crystal ball. Hmm, the result is blurry.

Thanks!