On July $1,2018,$ Tulsa Company pays $$600,000$ to acquire a fully equipped factory. The purchase involves the following assets and information. $(20$ points$)$

$\backslash$table$[[$Asset$,\backslash$table$[[$Appraised$],[$Value$]],\backslash$table$[[$Salvage$],[$Value$]],$Useful Life,Depreciation Method$],[$Land$,$$$160,000,,,$Not Depreciated$],[$Land Improvements,$80,000,0,10$ years,Straight$-$line$],[$Building$,320,000,100,000,10$ years,Double$-$declining$-$balance$],[$Machinery$,240,000,20,000,10,000$ units,Units$-$of$-$production $*],[$Total$,$$$800,000,,,]]$

$*$The machinery is used to produce $700$ units in $2018$ and $1,800$ units in $2019$

Required:

a$.$ Allocate the total $$600,000$ purchase cost among the separate assets.

b$.$ Compute the $2018($six months$)$ and $2019$ depreciation expense for each asset, and compute the company's total depreciation expense for both years.