$5.$ Calculate the mass of calcium carbonate $($CaCO$)$ needed to produce $1$ ton of calcium ammonium nitrate $($CAN$)[$Ca$($NO$)\mathrm{.}4$NH$$NO$],$ assuming the reaction efficiency is $95\%.$

$6.$ If a farmer needs to apply $20$ kg of sulfur per hectare and chooses to use ammonium sulfate $(($NH$)$SO$)$ as the source, how much ammonium sulfate should be applied?