geography: Which element makes up 5% of the Earth's crust ?

Questions

Snails have ----------. They are arranged in rows along the snail's tongue and are used like a file to saw or slice through the snail's foot.?

The electric organs in an electric eel make up four-fifths of its ----------?

So that it can pull its lithe body into a tight, prickly little ball for defense, the hedgehog has a large muscle running along its ----------?

Some ----------?

There is a substantial wild population of golden hamsters living in Eastern Europe and the Middle East. Scientists speculate that all the domesticated golden hamsters in the world descended from a single female with twelve babies, which were dug from a burrow in Syria back in ----------?