Final answer:
If one company gains ownership control of all uranium processing plants in the US, they can set up barriers to entry, there will be market demand and supply determining the price, and the government may regulate to prevent monopoly.
Step-by-step explanation:
If one company were to gain ownership control of all uranium processing plants in the US, several implications would arise. Firstly, this company could set up barriers to entry to discourage competition. These barriers could include legal restrictions, patent protection, and practices like predatory pricing. Secondly, the factors of market demand and supply would determine the price of uranium. Lastly, the government may step in and regulate the industry to ensure fair competition and prevent a monopoly.