"I work for a cell phone company here in town. As you are likely aware, over the past 10-20 years, the use of landline phones has fallen, while the use of cell phones and smartphones has increased. How can I determine equilibrium in this instance?"

"I farm on a small scale. Last year, I started off by planting soybeans and corn. This year, the price of soybeans increased, and the price of corn remained the same. Naturally, I planted more corn than soy. From your point of view, how does this explain the law of supply? From my first to my second year in farming, did the supply curve of corn or soybeans shift?"

"You may be aware that in the United States, price floors are commonly used to support farmers, such as for dairy products. Recently, several U.S. trading partners have imposed tariffs on dairy products exported from the United States. For the trading partners, the tariffs have been effective and are reducing dairy exports from the United States. The result is that the domestic equilibrium price of milk is now below the price floor. What I am curious about now is how these tariffs will change the U.S. domestic price of milk, the quantity of milk sold in the United States, and if this will result in a surplus or shortage of milk. Can you provide me with your best assessment of the situation?"