A distance of 200 ft. must be taped in a manner to ensure a standard deviation smaller than +0.04ft What must be the standard deviation (error) per 100 ft. tape length to achieve the desired precision

A line of three-wire differential levels goes from benchmark Gloria to benchmark Carey. The length of the line was determined to be 2097 m. The instrument had a stated compensator accuracy of pm 1.4 mm/ km. The instrument–rod combination had an estimated reading error of 0.4 mm per 40 m. Sight distances were kept to approximately 50 5 m. If the observed difference in elevation is 15.601 m, what is the estimated error in the final elevation difference? If benchmark Gloria had a fixed elevation of 231.071 m and Carey had a fixed elevation of 246.660 m, did the job meet acceptable closure limits at a 95% level of confidence? Justify your answer statistically.

A level loop was run and the raw elevations in Table 2 were calculated based on backsights and foresights. A plan view of the loop is shown in Figure 2. The true elevation of BM1 is 195.00 ft. Adjust the elevation of each station such that the error is evenly spaced. Show sample calculations of your work. Also determine the accuracy ratio of the survey. BM₁ 5 mi 3 mi BM2 BM4 3 mi BM3 4 mi Figure 2 Table 2 Station Raw Elevation [ft] BM1 195.0 BM2 205.6 BM3 209.8 BM4 204.7 BM1 195.5