discount list scenarios

hello everyone, I want to make a discount list for a specific scenario:

• if the sales order contains 10 unit from a specific item, they want to add 1 extra unit from this item to the customer for free.
• if the sales order for the customer contains a 10 unit of mixed items, the system should know the item with lowest price and add 1 extra unit from this item to the sales order for the customer.

is any of these scenarios is doable on the system??

Thanks in advance