E.I. du Pont de Nemours & Co. has an issue of $4.50 preferred stock outstanding. It is currently selling for $108. What rate of return are investors requiring?

To find the rate of return that investors are requiring for E.I. du Pont de Nemours & Co.'s preferred stock, you can use the dividend yield formula. The dividend yield is calculated by dividing the annual dividend payment by the current market price of the stock and expressing it as a percentage.

First, we need to determine the annual dividend payment. This can be done by multiplying the issue price of the preferred stock by its dividend rate. However, the dividend rate is not provided in the question.

To find the dividend rate, we need to calculate it as a percentage of the preferred stock's par value. Preferred stock is typically issued with a par or face value, which represents the stated value of the stock. In this case, the par value is not provided in the question.

Therefore, without the dividend rate or the par value, we cannot determine the annual dividend payment. As a result, we cannot calculate the rate of return that investors are requiring.