On an annual requirement of $100$ items spread evenly throughout the year, any purchaser has an opportunity of buying all $100$ units at a price of $$100$ each, or buying $10$ units at a time at a price of $$150.$ If the inventory carrying cost is $25$ percent per year and assuming no ordering costs

buying $100$ at a time will save the company $$6,250$ per year.

buying $100$ at a time will save the company $$4,125$ per year

buying $100$ at a time will save the company $$3,937\mathrm{.}50$ pear

buying $100$ at a time will save the company $$3,875$ per year.

buying $100$ at a time will lose the company $$875$ per year.