Jenny is planning to expand her business by taking on a new product. She can purchase the new product at a cost of $1.8 per unit. To market this new product, she would need to spend $1380 on advertising each month. She is not sure how she should price her product and is asking for your help. If she chooses a price of $16.8 per unit, what will be the contribution rate per unit? Note: leave 8 decimals in your final answer to receive the full mark