alexandra's boutique has the following transactions related to its top-selling gucci purse for the month of october. alexandra's boutique uses a periodic inventory system. date transactions units unit cost total cost october 1 beginning inventory 6 $750 $4,500 october 4 sale 4 october 10 purchase 5 760 3,800 october 13 sale 3 october 20 purchase 4 770 3,080 october 28 sale 7 october 30 purchase 6 780 4,680 $16,060