8 9 10 points A surveyor took 5 total measurements between points A and C The measured horizontal distances were 179 20 179 18 179 23 179 21 179 17 Calculate the mean of the horizontal distance measurements 179 20 197 20 179 22 179 18 10 points Calculate the standard deviation for question 7 0 024 0 035 0 011 0 020 D 10 points DES The same Total Station has specified errors of 3mm 2 ppm The instrument was centered over the survey point with an error of 4 mm The error of mis centering the target was 2 mm Compute the estimated error of the mean distance from Point A to Point C from question 8 4 79 mm 3 20 mm 6 18 mm 5 39 mm