For the 71 trading days from January 3, 2017, to April 18, 2017, the daily closing price of IBM stock (in $) is well modeled by a Normal model with mean $174.846 and standard deviation $4.509. According to this model, and using the 68-95997 Rule to approximate the probabilities rather than using technology to nd the values more precisely, what is the probability that on a randomly selected day in this period the stock price closed a) above $183.86? b) below $179.36? c) between $161.32 and $188.37? d) Which would be more unusual, a day on which the stock price closed above $187 or below $170? (E a) The probability that the stock price closed above $183.86 is E. (Type an integer or a decimal. Do not round.)