1-For multipoint configuration, only one device at a time can transmit. Why and

1-For multipoint configuration, only one device at a time can transmit. Why and what is that terminology called. Explain in maximum 2 paragraphs and cite your work? (10 Point)
2- Cost-2-Cost is a famous radio show broadcast from Los Angeles, California. The broadcast use AM stereo at 1320 kHz by the time it reaches Maryland, Rockville WWDC-F2 (@101.1 kHz) Monday – to Saturday from 1AM to 6AM and Sunday off day. What is the antenna height required to capture the station wavelength. Explain your Answer and calculations in details Do Not give only the final answer or short explanation you will not get a grade. (10 points)
3- Hulu and YouTube offer regular TV broadcast, and Time Shift service for their customers. As promotion to encourage subscribers to the service providers. FXX movie channel broadcast a new 4K movie with Dolby Atmos for subscribers. Answer the following Questions and Explain your Answer and calculations in details Do Not give only the final answer or short explanation you will not get a grade. (20 points)
What is the required bandwidth to watch a 4K HDR10 12-Bit color movie stream? (10 points)
How much data is needed for the Time Shift of 1.5 hour and what is the compressed Value in? (10 points
Need to explain the details the steps of your answer and calculations.
Need to mention references and citations for all the above questions