Elder et al. (2004) analyzed the prevalence and characteristics of alcohol-related hospital visits among a sample of emergency departments and found frequent visits related to assault. Suppose that you gather a random sample of 190 records from the files of young adults charged with assault over the past six months. You find that the mean age of those charged is 20.8 years with a standard deviation of 3.1 years. Use these statistics to calculate the standard error of a sampling distribution of ages.