2 (iii) Assume that management estimates that cost to investigate a variance as $700, the cost to correct the cause of a controllable variance as $200, and the probability that any variance (regardless of size) is due to a correctable cause as 25%. Assume further that management estimates that the loss from failure to discover a correctable cause of a variance averages 80% of the size of the variance. For example, the loss for the failure to discover a correctable $5,000 variance would be $4,000, the loss from the correctable $9,000 variance would be $7,200, and so forth. Required: Determine the minimum size of a variance that justifies investigation. (6 marks)