Apsycho-linguist has been studying the frequency of text-speech (e. g., r u ok? , lol ) has been progressing into email correspondence. he collects a sample of 100 email messages and computes the mean (average) number of examples of text-speech per message. he also has a huge library of archived email messages from the year 2001. from these he is able to calculate the population average and standard deviation. compute a inferential statistic to evaluate the hypothesis that the use of text-speech has increased in the years since 2001. use an alpha level that would insure a maximum of a %5 risk of rejecting a true null hypothesis. these are the obtained values: population mean from 2001: 1.7 population standard deviation from 2001: 1.26 sample mean from this year: 1.95 the appropriate statistics to use is a test.