1. Describe the difference between a model and a simulation 2. What model do you use for the following system? Categorize it using each of the four model characteristics. An investment company has $1 million to invest in five different asset classes (e.g., short-term treasury notes, stocks, bonds, etc.). The company must consider the return and risk of each asset class. Return is usually measured as the expected value of the return over some time horizon (e.g., a year). Risk is usually measured as the standard deviation of return over the same time horizon. The company wants to maximize its return while limiting risk to a set level