Na$2$SO$4.10$H$2$O crystals are formed by cooling $100$ Kg of $30\%$ by weight aqueous solution of Na$2$SO$4.$ The final concentration of the solute in the solution is $10\%.$ The weight of crystals is

$20$

$32\mathrm{.}2$

$45\mathrm{.}35$

$58\mathrm{.}65$