The article “The Epiphytic Lichen Hypogymnia physodes as a Bioindicator of Atmospheric Nitrogen and Sulphur Deposition in Norway” (Environmental Monitoring and Assessment [1993]: 27–47) gives the following data (read from a graph in the paper) on x = NO₃ wet deposition (in grams per cubic meter) and y = lichen (% dry weight):

a. What is the equation of the least-squares regression line?

b. Predict lichen dry weight percentage for an NO₃ deposition of 0.5 g/m³.

Transcribed Image Text:

X 0.05 y 0.48 X y X y 0.37 0.52 0.10 0.55 0.42 1.02 0.11 0.48 0.58 0.86 0.73 0.85 0.92 0.88 1.04 1.70 0.12 0.50 0.68 0.86 0.31 0.58 0.68 1.00