7.26 Antibiotic consumption, Part II. Antibiotic consumption, Part II. Exercise 7.22 introduced a study conducted about antibiotic consumption in China. One aim of the study was to develop a prediction model for predicting monthly average antibiotic consumption based on county-level data. The following plots show the association between monthly average antibiotic consumption and four potential predictor variables: proportion female inhabitants (female), average life expectancy in years (lifeexp), proportion of population illiterate (illiterate), and population density in 1,000 people / km2 (popdensity). (a) Summarize what you see. (b) Identify any predictor variables that might benefit from a natural log transformation and briefly justify your choices