Add a running sum to a query in Access

I have two tables "tblInventoryTransaction" and "InventoryTransactionDetail". In this table I enter the Inventory transactions. I want to create a query that use this two tables and show all transactions that did in stock. I need this query to sum all quantity of a inventory item until now and the total price paid for all of the inventory purchased as new column with running sum.

I need this running sum of inventory quantity and total paid for an inventory for a calculation. How can I add this running sum to my query.