Three crews level to a benchmark following three different routes. The lengths of the routes and the observed differences in elevation are Route Elev (ft) Length (ft) 1 14.80 2500 2 14.87 5000 3 14.83 3600

a) What is the best value forthe difference in elevation?

b) what is the standard deviation for the elevation difference?

c) What are the standard deviation for the weighted obervation?

d) Compute the standard deviations for the weighted deviations?