# #NA - ERROR handle in formula

Assume three columns **A**, **B** and **C**. Columns **A** and **B** can contain **text**, **numeric values** or **#NA**.

Column **C** should summarize the columns **A** and **B**

eg *If*`A2=123`

and `B2=#NA`

the result in `C2=123`

*or If*`A2=#NA`

and `B2=K2-123`

the result in `C2=K2-123`

*or if*`A2=#NA`

and `B2=#NA`

the result in `C2=`

(empty cell)

*or if*`A2=123`

and `B2=K2-123`

the result in `C2=123`

(the same as cell A2)

Is it possible to handle **#NA** in a formula?