Here is the question:

, 4, and 16. Careful examination of photoimagery of the rst and third of these plots (selected as a simple random subsample) revealed the actual presence of 56 and 6 ducks, respectively. The study area consists of 10 plots. (a) Estimate the total number of ducks in the study area by using a ratio estimator. Estimate the variance of the estimator. (b) Suppose that the photo analysis doubles the cost of observing a plot. Esti mate the optimal subsampling fraction