What is the reorder point?

Burger Q sells about 500 DoubleHappinness burgers daily. It is their
trademarked star seller that is a double burger.  As their customers
are rather unpredictable, they need to carry extra 750 burgers.
Burger Q buys the patties from John’s Farm, who can deliver them in 3
days, at 25 cents each plus $80 flat-rate charge.  Financing comes
from Bank Krupt at 10% per year
What is the reorder point?