Company B wants to raise$20 million via an initial public offering(IPO). They contact Bank XYZ for underwriting services. Bank XYZ explains that there are three types ofunderwriting: abest-efforts IPO, a firm commitment IPO and an auction IPO. Which type of underwriting is riskiest to the underwriter and which type of underwriting that Bank XYZ will charge the highestspread? Briefly explain thereason(s).