please give me how to do the answer. not only the option. thank you

Use the following to answer questions 6 & Bloomburg Company's management believes that every 9% decrease in the selling price of one of the company's products would lead to a 15% increase in the product's total unit sales. The product's variable cost is $11.80 per unit. 6. The product's price elasticity of demand as defined in the text is closest to: A) -1.12 B) - 1.34 C) -1.61 D) -1.48 7. The product's profit-maximizing price according to the formula in the text is closest to: A) $31.19 B) $46.07 C) $106.31 D) $36.28