BJ and Taylor are green home designers who are producing a webinar to share knowledge of green building. Web conferencing requires only a PC and an internet connection; however, audio conferencing capability is required to chat with attendees by telephone. They are working with a webinar hosting company that charges 10 cents per participant/ per minute (ppm) for web conferencing, 15 cents ppm for audio conferencing, and $175 for online registration support. Although they will present some content, they will hire a professional speaker who is an expert on wind turbines for home use, and will include audio conferencing so that attendees can interact with the speakers. The registration fee for a 60-minute webinar is $159. Create the Excel spreadsheet shown in Figure 8.20 to determine the number of attendees required to make a profit. How does that number change if the registration fee is reduced to $149? Use formulas for all calculations and Goal Seek to set profit to $1 by changing the number of attendees. If the registration fee is reduced is $159, how many attendees are required to make a profit of $10,000?