A portfolio management organization analyzes 60 stocks and constructs a mean-variance efficient portfolio using only these 60

Question:

A portfolio management organization analyzes 60 stocks and constructs a mean-variance efficient portfolio using only these 60 securities.

a. How many estimates of expected returns, variances, and covariances are needed to optimize this portfolio?

b. If one could safely assume that stock market returns closely resemble a single-index structure, how many estimates would be needed?

Stocks
Stocks or shares are generally equity instruments that provide the largest source of raising funds in any public or private listed company's. The instruments are issued on a stock exchange from where a large number of general public who are willing... Portfolio
A portfolio is a grouping of financial assets such as stocks, bonds, commodities, currencies and cash equivalents, as well as their fund counterparts, including mutual, exchange-traded and closed funds. A portfolio can also consist of non-publicly...