COL. A& B OREADY INSERT 

My sample data:

```
A          B           K       P       M
--         --         --       --      -- 
2          5                       
3          5                  

```

Query:

```
select  
    ([A] + [B]) AS [K], 
    ([A] * [B]) AS [P],
    -- can I write like this?
    ([P]-[K]) AS [M] 
    -- or must I write :
    -- ([A]+[B]) - ([A]*[B]) /* sometimes the formula is very long
from  
    TB

```