EOQ vs Bulk Discount

1) Is it true that when calculating BULK discount order we have to compare that with the EOQ order policy to evaluate how much we saved from the BULK discount?

2) And if we are given more than one order with different quantities being used then we have to calculate each of them individually but in the end, we’ll compare that to the EOQ policy?

3) Is this the correct way to calculate the Cost of Buffer Stock such as:

Buffer Stock (units) x Cost of Holding each unit

Please correct me If I am wrong