Refer to the data table. The H column reports estimated standard deviations for each measurement. How might you use these to estimate varH ? Write an approach by listing a few steps, and explain the reasoning.

Supernova data from Freedman et al. Supernova ID Velocity (km/sec) Distance (Mpc) H (km/sec/Mpc) OH SN19900 9065.00 134.70 67.30 2.30 SN1990T 12012.00 158.90 75.60 3.10 SN 1990af 15055.00 198.60 75.80 2.80 SN 1991S 16687.00 238.90 69.80 2.80 SN1991U 9801.00 117.10 83.70 3.40 SN199lag 4124.00 56.00 73.70 2.90 SN1992.J 13707.00 183.90 74.50 3.10 SN 1992P 7880.00 121.50 64.80 2.20 SN 1992ae 22426.00 274.60 81.60 3.40 SN 1992ag 7765.00 102.10 76.10 2.70 SN1992al 4227.00 58.00 72.80 2.40 SN 1992aq 30253.00 467.00 64.70 2.40 SN 1992au 18212.00 262.20 69.40 2.90 SN 1992bc 5935.00 88.60 67.00 2.10 SN 1992bg 10696.00 151.40 70.60 2.40 SN1992bh 13518.00 202.50 66.70 2.30 SN1992bk 17371.00 235.90 73.60 2.60 SN1992bl 12871.00 176.80 72.70 2.60 SN 1992bo 5434.00 77.90 69.70 2.40 SN 1992bp 23646.00 309.50 76.30 2.60 SN1992br 26318.00 391.50 67.20 3.10 SN 1992bs 18997.00 280.10 67.80 2.80 SN1993B 21190.00 303.40 69.80 2.40 SN19930 15567.00 236.10 65.90 2.10 SN 1993ag 15002.00 215.40 69.60 2.40 SN 1993ah 8604.00 119.70 71.90 2.90 SN 1993ac 14764.00 202.30 72.90 2.70 SN1993ae 5424.00 71.80 75.60 3.10 SN1994M 7241.00 96.70 74.90 2.60 SN1994Q 8691.00 127.80 68.00 2.70 SN1994S 4847.00 66.80 72.50 2.50 SN1994T 10715.00 149.90 71.50 2.60 SN1995ac 14634.00 185.60 78.80 2.70 SN 1995ak 6673.00 82.40 80.90 2.80 SN19960 9024.00 136.00 66.30 2.50 SN1996bl 10446.00 132.70 78.70 2.70 Table 1: Velocity and distance measurements for 36 type la supernovae. Data from Freedman, Wendy L., et al. "Final results from the Hubble Space Telescope key project to measure the Hubble constant." The Astrophysical Journal 553.1 (2001): 47