How does it (Cost of Equity Capital) differ from Cost of Preferred capital/stock?

 Cost of Equity Capital:In finance, the cost of equity is the return a firm theoretically pays to its equity investors, i.e., shareholders, to compensate for the risk they undertake by investing their capital. Firms need to acquire capital from others to operate and grow.// 

Cost of Preferred capital/stock:Cost of preferred stock is the cost that the company has committed to pay to the preferred stockholders in the form of preferred dividends.