I know the margin formula is net operating income / sales, but I'm having a hard time figuring out the correct number for net operating income in the formula.

Westerville Company reported the following results from last year's operations:

Sales$1,800,000

Variable expenses740,000

Contribution margin1,060,000

Fixed expenses700,000

Net operating income$360,000

Average operating assets$1,200,000

At the beginning of this year, the company has a $400,000 investment opportunity with the following cost and revenue characteristics:

Sales $600,000

Contribution margin ratio60% of sales

Fixed expenses $288,000

The company's minimum required rate of return is 10%.

4. What is the margin related to this year's investment opportunity?