I need help with these 9 microeconomics questions:

Part I. Price Elasticity of Demand: Use the following information to answer the next 5 questions. Anna's demand for brownies is Q1: 90 4P. Question 1 (0.2 points) b. Calculate the price elasticity as the price moves from P0 = 20 to P1 = 15 by using the mid-point price elasticity formula (hint: this is the same formula as the arc elasticity formula). E= [Blank 1] Round off your answer to two decimal places :1 Question 2 (0.1 points) c. Calculate the total revenue (TR) at P = 20 and P = 15 separately. When P = 20, TR = [Blank 1]; when P = 15, TR = [Blank 2]. Round off your answer to the nearest integer Does the total revenue (TR) increase, decrease, or stay the same when the price decreases from P = 20 to P = 15? Since the price is [Blank 3: type either "elastic" or "inelastic"] at P = 20, a decrease in price will cause the total revenue to [Blank4: "increase" or "decrease"]. Blank # 3 Blank # 4 [] Question 3 (0.1 points) d. Use your calculation of the price elasticity of demand at these two different prices to explain the result in the change of total revenue. Question 4 (0.1 points) e. At what price is the price elasticity of demand equal to 1? P = $[Blank 1] Round off your answer to two decimal places. Question 5 (0.1 points) f. Complete the table below based on Anna's demand for brownies which is Qd= 90 4P. Elasticity TR(=PxQd) Round off your answer to two decimal places. When the elasticity Ep > 1: if the price increases, does the total revenue increase, decrease, or remain unchanged? [Blank 6: type either "increase", "decrease", or "remain unchanged"] . When the elasticity Ep