please solve 5 and 6, also do not use excel solve it out through writing and step process please

Thank you :)

5. An investor in a 28% tax bracket is tyying to decide whether to invest in a municipal bond or a corporate bond. She looks up municipal bond yields ( (a) but wishes to calculate the taxable equivalent yieldr. The formula she should use is given by A. r=7(128%) B. r=(172%) C. r=a(172%) D. r=r(128%) 6. The Hydro Index is a price welghted stock inder based on the 5 largest boat manufacturers in the nation. The stock prices for the five stocks are $10,$20,$80,$50 and S40. The price of the last stock was just split 2 for 1 and the stock price was halved from $40 to $20. What is the new divisor for a price weighted index? A. 5.00 B. 4.85 C. 4.50 D. 4.75