The following spreadsheet contains monthly returns for Cola Co. and Gas Co. for 2010. (You do NOT need to fill out the empty cells here again).
				Realized Returns
			Date	Cola Co	Gas Co.	Portfolio of 55% Cola and 45% Gas
			Jan	-10.84%	-6.00%
			Feb	2.36%	1.28%
			Mar	6.60%	-1.86%
			Apr	2.01%	-1.90%
			May	18.36%	7.40%
			Jun	-1.22%	-0.26%
			Jul	2.25%	8.36%
			Aug	-6.89%	-2.46%
			Sep	-6.04%	-2.00%
			Oct	13.61%	0.00%
			Nov	3.51%	4.68%
			Dec	0.54%	2.22%
			Average return
			Volatility
		Part I: calculate the correlation coefficient between Cola and Gas?
		Part II: use the equation on LC9 Slide #17 to calculate portfolio volatility again, and compare with your calcuation from #2.