An industrial park is being planned for a tract of land near the river. To prevent flood damage to the industrial buildings that will be built on this low-lying land, an earthen embankment can be constructed. The height of the embankment will be determined by an economic analysis of the costs and benefits. The following data have been gathered. Rate of return is 12%. Overflood causes $300,000 of damage. If embankment is necessary, how high should it be? The life of embankment is expected to be 50 years.