CFO = 765 + 184 - 69 - 54 - 83 - 37 + 55 + 33 = 794. Gain or loss on sale of assets is CFI, not CFO.

The combination, or binomial formula, gives the number of ways that k objects can be chosen from n items, without regard to the order of choosing. The formula is (n choose k) = n! / [k! *(n-k)!].
However, in this case, the order does matter. If we choose stocks 3, 1, 7, and 5, we don't consider that the same as choosing 5, 7, 1 and 3, because the portfolio weights would differ. We need the general permutation formula, which gives the number of ways that k objects can be chosen from n items, with regard to order. The formula is n_P_k = n! / (n-k)!. Here, it is 8! / (8-4)! = 8 * 7 * 6 * 5 = 1,680.

A random variable is a quantity whose outcome is uncertain.

Expectations do not change LRAS since it is determined by technology, resource base and institutional factors.

Frequency distributions are used to summarize rates of return. They do work with ratio scales. Frequency distributions can be used with any kind of measurement scale.