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A civil engineer has been studying the frequency of vehicle accidents on a certain stretch of interstate highway. Long-term history indicates that there has been an average of 1.8 accidents per day on this section of the interstate. Let r be a random variable that represents number of accidents per day. Let O represent the number of observed accidents per day based on local highway patrol reports. A random sample of 92 days gave the following information. 0 2 3 4 or more O 19 24 17 17 15 The civil engineer wants to use a Poisson distribution to represent the probability of r, the number of accidents per day. The Poisson distribution is P(r) = A' where A = 1.8 is the average number of accidents per day. Compute the sample statistic. X2 =[ (0-F)? O 6.553 0.460 11.262 O 14.474 O 7.944