T-SQL (SS2K8) :: Calculate On Newly Created Columns

I have a table that I have created a table and desire to do some basic math by adding a few new columns. The problem is that i cant get this to work without create many new select statements. The new columns that I wish to add refer to other newly created columns. Is there a way I can do this with CTW or subqueries? Unless it is a best practice to chain out the logic for the newly created columns

I have an example from AdventureWorksDW since the data is very accessible. I can safely create EMP_TENURE and PTO_REMAINING is this select statement. I would then need to create a new select statement to define 'BONUS' and then another select statement to define 'NEW_COL1' and so on.

Im still pretty new at SQL and am trying to learn how to complete such a task using subqueries or CTE.

SELECT
NAME = [LastName] + ',' + [FirstName]
,HireDate
,Title
,DepartmentName
,BaseRate
,VacationHours
,SickLeaveHours

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