You have $36,000 to invest in Sophie Shoes, a stock selling for $60 a share. The initial margin requirement is 65 percent. Do not round intermediate calculations. Round your answers to two decimal places. Use a minus sign to enter negative values, if any. a. Ignoring taxes and commissions, calculate your rates of return if the stock rises to $90 a share and if it declines to $40 a share assuming you pay cash for the stock. Rate of return if the stock rises to $90 a share: Rate of return if the stock declines to $40 a share: % b. Ignoring taxes and commissions, calculate your rates of return if the stock rises to $90 a share and if it declines to $40 a share assuming you buy it using maximum leverage. Rate of return if the stock rises to $90 a share: Rate of return if the stock declines to $40 a share: % %