As an assistant to Rachel, you are asked to collect the monthly prices of each stock from Yahoo Finance from 11/23/2010 to 11/2/2015 (market booming time period), and then finish the following tasks: (Johnson and Johnson, IBM, Boeing) Please show the formula and/or work

1. Calculate monthly returns for each stock

2. 3. Calculate the variance and average return for each stock

4. Construct the covariance matrix of these stocks

5. Use Excel Solver function to build the efficient frontier (with and without short sale)

6. Determine the optimal risk portfolio

7. Draw a graph showing the efficient frontier and the CAL line (one graph for the case with short sale and one graph without short sale)

Boeing

Date	Open	Close
11/2/2015	148.380005	148.399994
10/1/2015	131.320007	148.070007
9/1/2015	128.160004	130.949997
8/3/2015	144.440002	130.679993
7/1/2015	140.479996	144.169998
6/1/2015	141.449997	138.720001
5/1/2015	144.410004	140.520004
4/1/2015	149.970001	143.339996
3/2/2015	150.850006	150.080002
2/2/2015	143.720001	150.850006
1/2/2015	131.070007	145.369995
12/1/2014	134.309998	129.979996
11/3/2014	125.349998	134.360001
10/1/2014	127.370003	124.910004
9/2/2014	125.620003	127.379997
8/1/2014	120.449997	126.800003
7/1/2014	127.660004	120.480003
6/2/2014	135.5	127.230003
5/1/2014	128.740005	135.25
4/1/2014	126.239998	129.020004
3/3/2014	127.18	125.489998
2/3/2014	124.239998	128.919998
1/2/2014	136.009995	125.260002
12/2/2013	134.990005	136.490005
11/1/2013	130.899994	134.25
10/1/2013	117.970001	130.5
9/3/2013	105.129997	117.5
8/1/2013	105.989998	103.919998
7/1/2013	102.93	105.099998
6/3/2013	99.360001	102.440002
5/1/2013	91.080002	99.019997
4/1/2013	85.599998	91.410004
3/1/2013	76.699997	85.849998
2/1/2013	74.489998	76.900002
1/2/2013	76.550003	73.870003
12/3/2012	74.410004	75.360001
11/1/2012	70.589996	74.279999
10/1/2012	69.860001	70.440002
9/4/2012	71.5	69.599998
8/1/2012	74.32	71.400002
7/2/2012	74.209999	73.910004
6/1/2012	68.669998	74.300003
5/1/2012	76.589996	69.610001
4/2/2012	74	76.800003
3/1/2012	74.959999	74.370003
2/1/2012	74.959999	74.949997
1/3/2012	74.699997	74.18
12/1/2011	68.699997	73.349998
11/1/2011	64.230003	68.690002
10/3/2011	60.099998	65.790001
9/1/2011	66.959999	60.509998
8/1/2011	71.610001	66.860001
7/1/2011	73.809998	70.470001
6/1/2011	77.949997	73.93
5/2/2011	80.349998	78.029999
4/1/2011	74.290001	79.779999
3/1/2011	71.93	73.93
2/1/2011	70	72.010002
1/3/2011	66.150002	69.480003
12/1/2010	64.660004	65.260002
11/23/2010	63.43	63.77

IBM

Date	Open	Close
11/2/2015	140.5	140.369995
10/1/2015	145.309998	140.080002
9/1/2015	144.910004	144.970001
8/3/2015	161.699997	147.889999
7/1/2015	163.970001	161.990005
6/1/2015	170.210007	162.660004
5/1/2015	173.199997	169.649994
4/1/2015	160.229996	171.289993
3/2/2015	161.940002	160.5
2/2/2015	154	161.940002
1/2/2015	161.309998	153.309998
12/1/2014	161.639999	160.440002
11/3/2014	164.25	162.169998
10/1/2014	189.910004	164.399994
9/2/2014	192.679993	189.830002
8/1/2014	190.5	192.300003
7/1/2014	181.699997	191.669998
6/2/2014	184.759995	181.270004
5/1/2014	196.309998	184.360001
4/1/2014	193.119995	196.470001
3/3/2014	183.330002	192.490005
2/3/2014	176.020004	185.169998
1/2/2014	187.210007	176.679993
12/2/2013	179.460007	187.570007
11/1/2013	179.809998	179.679993
10/1/2013	185.339996	179.210007
9/3/2013	183.630005	185.179993
8/1/2013	196.649994	182.270004
7/1/2013	192.149994	195.039993
6/3/2013	208.25	191.110001
5/1/2013	201.869995	208.020004
4/1/2013	212.800003	202.539993
3/1/2013	200.649994	213.300003
2/1/2013	204.649994	200.830002
1/2/2013	194.089996	203.070007
12/3/2012	190.759995	191.550003
11/1/2012	194.679993	190.070007
10/1/2012	208.009995	194.529999
9/4/2012	196.610001	207.449997
8/1/2012	196.960007	194.850006
7/2/2012	196.360001	195.979996
6/1/2012	190.119995	195.580002
5/1/2012	207.179993	192.899994
4/2/2012	208.960007	207.080002
3/1/2012	197.229996	208.649994
2/1/2012	193.210007	196.729996
1/3/2012	186.729996	192.600006
12/1/2011	187.009995	183.880005
11/1/2011	181.550003	188
10/3/2011	174.360001	184.630005
9/1/2011	172.710007	174.869995
8/1/2011	182.600006	171.910004
7/1/2011	171.610001	181.850006
6/1/2011	168.899994	171.550003
5/2/2011	172.110001	168.929993
4/1/2011	163.699997	170.580002
3/1/2011	163.149994	163.070007
2/1/2011	162.110001	161.880005
1/3/2011	147.210007	162
12/1/2010	143.610001	146.759995
11/23/2010	144.240005	141.460007

Johnson and Johnson

Date	Open	Close
11/2/2015	101.18	102.169998
10/1/2015	93.43	101.029999
9/1/2015	92.290001	93.349998
8/3/2015	100	93.980003
7/1/2015	98.300003	100.209999
6/1/2015	100.279999	97.459999
5/1/2015	99.620003	100.139999
4/1/2015	100.459999	99.199997
3/2/2015	102.510002	100.599998
2/2/2015	100.489998	102.510002
1/2/2015	105.050003	100.139999
12/1/2014	107.889999	104.57
11/3/2014	107.830002	108.25
10/1/2014	105.980003	107.779999
9/2/2014	103.300003	106.589996
8/1/2014	99.760002	103.730003
7/1/2014	105.150002	100.089996
6/2/2014	101.540001	104.620003
5/1/2014	100.769997	101.459999
4/1/2014	98.309998	101.290001
3/3/2014	91.129997	98.230003
2/3/2014	88.75	92.120003
1/2/2014	91.139999	88.470001
12/2/2013	94.410004	91.589996
11/1/2013	92.379997	94.660004
10/1/2013	86.589996	92.610001
9/3/2013	86.889999	86.690002
8/1/2013	94.160004	86.410004
7/1/2013	85.720001	93.5
6/3/2013	84.279999	85.860001
5/1/2013	84.5	84.18
4/1/2013	81.389999	85.230003
3/1/2013	75.790001	81.529999
2/1/2013	74.139999	76.110001
1/2/2013	71.019997	73.919998
12/3/2012	69.800003	70.099998
11/1/2012	71.099998	69.730003
10/1/2012	68.919998	70.82
9/4/2012	67.489998	68.910004
8/1/2012	69.480003	67.43
7/2/2012	67.419998	69.220001
6/1/2012	62.040001	67.559998
5/1/2012	64.910004	62.43
4/2/2012	66.040001	65.099998
3/1/2012	65.110001	65.959999
2/1/2012	65.970001	65.080002
1/3/2012	65.589996	65.910004
12/1/2011	64.68	65.580002
11/1/2011	63.68	64.720001
10/3/2011	63.650002	64.389999
9/1/2011	65.660004	63.689999
8/1/2011	65.279999	65.800003
7/1/2011	66.480003	64.790001
6/1/2011	67.019997	66.519997
5/2/2011	65.919998	67.290001
4/1/2011	59.630001	65.720001
3/1/2011	61.25	59.25
2/1/2011	59.700001	61.439999
1/3/2011	62.630001	59.77
12/1/2010	62.18	61.849998
11/23/2010	62.990002	61.549999