a$.)$ ladies boot vendor is offering a quantity discount to a factory store buyer of $40\%$ off based on purchasing $1000$ units or more of assorted products. What is the original cost of this order versus the discounted costa$.$Short boots $400$ pcs at original price of $$90$

b$.)$Tall boots $600$ pcs at $$140$ original price

$1.$Original Cost

$2.$Discount Cost