(h) When we apply mean-variance framework to help us make an investment decision, we are choosing assets provide higher expected rate of return for a certain level of volatility (variance). Expected rate of return is a forward looking variable that we may never know it realized value. However, an asset X1,2000-2021 is backward looking variable that we may already have all of its value in mind. If we want use X1,2000-2021 to predict E (X1,2022). Does {X1,2000, X1,2001, ..., X1,2021, X1,2022) need to be based on the same distribution? Why