Question

what is a crust...........

Answer 1

IT IS A LAYER OF Land BRO

Or more clearly

the crust is the outermost solid shell of a rocky planet, dwarf planet, or natural satellite...

$| \leqslant < regards \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: akshat \: rajput \geqslant > |$

Answer 2

the hard part on the outside of a piece of bread, a pie, etc.