A landscape ecology study investigated the characteristics of a number of plots of prairie land. For each plot they measured the "length of edge" and the number of species. The data are presented below, along with some summary statistics.

Length of edge (x): 18 10 13 29 16 1322 9 32

Number of species (y): 7 10 14 28 12 9 10 11 25

xi = 162, yi = 126, xiyi = 2648, xi2= 3448, yi2= 2200.

a)Consider the regression line relating y to x. Calculate the least squares estimates of the slope and intercept for the regression line relating number of species to length of edge (i.e. relating y to x)?

b)Perform a test of the hypothesis H0 : b1 = 0 versus the two-sided alternative.

c)Perform a test of the hypothesis H0 : b1 = 10 versus the two-sided alternative.

d)The investigators plan to continue to examine additional plots of prairie land. If, tomorrow, they should find a plot whose length of edge is 13, give a prediction of the number of species in that plot, and give a 90% confidence interval for your prediction