The article " The statistics of phytotoxic Air Pollutants" suggests the lognormal distribution as a model for SO2 concentration above a certain forest. suppose the parameter values are = 1.9 and = 0.9 (a) What is the standard deviation of 2 concentration above a certain forest? (b) What is the probability that 2 concentration above a certain forest is between 5 and 10? (c) What is the value such that only 5% of all 2 concentration above a certain forest exceeds this c?.