Review the textbook and watch the mini-lectures, taking careful notes. Then, respond to the following: Open your spreadsheet with the TLT and VTI risk/return analysis from the last discussion. Add a column to calculate monthly portfolio returns assuming a portfolio allocation that is 90% TLT and 10% VTI. Calculate the portfolio's average monthly percentage returns, standard deviation of monthly percentage returns, and CoV. Optional: Compare the risk, return and CoV of alternative portfolio allocations e.g., 100% TLT/0% VTI; 80% TLT/20% VTI; etc. Which has the best CoV? Optional: Calculate and share the correlation of TLT and VTI. How does a low correlation explain your results?