a•(b-m+n)

The expression \( a \cdot (b - m + n) \) represents the product of \( a \) and the quantity \( (b - m + n) \).

To simplify or manipulate this expression, you can distribute \( a \) to each term inside the parentheses:

\[ a \cdot (b - m + n) = a \cdot b - a \cdot m + a \cdot n \]

This can be written as:

\[ ab - am + an \]

If you have a specific context or further instructions for using or manipulating this expression, please let me know!