help please & thank you

Last year, Cayman Corporation had sales of $27 million, total variable costs of $13 million, and total fixed costs of $5,000,000. In addition, they paid $3 million in interest to bondholders. Cayman has a marginal tax rate of 21 percent. If Cayman's sales increase by 15%, what should be the increase in operating income? SET YOUR CALCULATOR TO 4 DECIMAL PLACES THEN ROUND TO 2 DECIMAL PLACES AT THE END. DO NOT ENTER THE \% SIGN. FOR EXAMPLE, IF YOUR ANSWER IS 12.7125, ENTER IT AS 12.71