Use Expressions and Formulas

IF(IsNull(ProductName), "data missing", ProductName)

IF(IsNull(ProductName),"gray","black")

IF(LTE(Quantity, 6), "restock")

IF(LTE(Quantity,6),"orange")

Multiply(UnitPrice,Quantity)

Sum(Multiply(UnitPrice,Quantity))

Add(Freight,Sum(Multiply(UnitPrice,Quantity)))