a$.$ The database contains three tables containing information about this company's sales process: Inventory, Sales, and Salesitems. Use the Relationships window to link the tables together.

b$.$ The Salesitems table records the quantity and price of each item sold on each sale $($sales may include more than one item$).$ Calculate the extended amount of sale $($call it Amt$)$ for each item $($Quantity $*$ UnitPrice$).$ Include InvoiceID, InventoryID, Quantity, and UnitPrice in the query. Name the query Item$\_$Extension$\_$Calculation.

c$.$ Calculate the total dollar amount of each sale. Include InvoicelD, InvoiceDate, CustomerID, and EmployeelD from the Sales table

d$.$ Calculate total sales for each inventory item.

e$.$ Calculate total sales.

f$.$ Calculate the month in which each sale occurred. Include InvoicelD and InvoiceDate from the Sales table. Name the query Sales$\_$Months. $($Hint: Look for the Month function in the expression builder.$)$

g$.$ Calculate the sum of sales for each month.