A company's inventory records indicate the following data for the month of January:

$\backslash$table$[[$Date$,$Activities,Units Acquired at Cost,Units Sold at Retail$],[$January $1,$Beginning inventory,$450$ units @ $$18=$$$8,100,],[$January $8,$Purchase,$430$ units @ $$20=$$$8,600,],[$January $12,$Sale,$490$ units @ $$22=$$$10,780,780$ units @ $$70$