13. (20 points) Kreter, Inc. earned net income of $300,000 last year. This year it wants to eam net income of $450,000. The company's fixed costs are expected to be $300,000, and variable costs are expected to be 70% of sales. Instructions (a) Determine the required sales to meet the target net income of $450,000 using the (b) Using a CVP income statement format, prove your answer. mathematical equation