Dragging a Board problem, fairly simple yet somehow I am getting it wrong?

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The problem involves a uniform board transitioning between two regions with different coefficients of kinetic friction. The initial friction force acting on the board is calculated using the coefficient from region 1, while the final force uses the coefficient from region 2. The work done on the board should be represented as the area under a force versus distance graph, indicating that it lies between the two calculated friction forces. The user is uncertain about their solution and seeks clarification on the setup and calculations. Proper visualization of the forces and distances involved is essential for accurately determining the work done.
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Homework Statement



A uniform board of length and mass lies near a boundary that separates two regions. In region 1, the coefficient of kinetic friction between the board and the surface is , and in region 2, the coefficient is . The positive direction is shown in the figure.



Homework Equations



Wnet= -[(M*g*mu1*L)+(M*g*mu2*L)]



The Attempt at a Solution





^^^^^^ wouldn't that be my solution above? computer is teling me that I am wrong.
 
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Initially the board is in μ1 territory and it gets pulled into μ2 territory, right?
Is it stretched out perpendicular to the boundary?
If so, initially the force of friction is mg*μ1. After pulling the full length of the board, the force of friction is mg*μ2. So the work should be somewhere between mg*μ1*L and mg*μ2*L.

I would suggest sketching a graph of force vs distance. The area under this graph will be the work done.
 
where is the figure?
 

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