Answer:
$600,000
Explanation:
The value added of the firm is the difference between the selling price of the ouput, and the costs of the inputs that were used to produce that output.
In this case, the output was sold for a total of $1,000,000, and the firm purchased $400,000 worth of raw materials, therefore, the firm's value added to GDP is = $1,000,000 - $400,000
= $600,000