Microeconomics questions.

When constructing a demand curve for a certain product, what is kept constant? Explain why a demand curve slopes right and downward. Please provide all of the variables.

Is strategic management's position evolving in the era of Industry 4.0, given existing economic processes?

Has the use of Dynamics Stochastic General Equilibrium modeling aided the development of our monetary policy?

During this Covid-19 pandemic, how can you define a long-run equilibrium in an endowment economy with perfect competition. Incorporate it into a diagram/table.