Montarello and Martens (2005) found that fifth-grade students completed more mathematics problems correctly when simple problems were mixed in with their regular math assignments.  To further explore this phenomenon, suppose that a researcher selects a standardized mathematics achievement test that produces a normal distribution of scores with a mean of u=100 and a standard deviation of o=18.  The researcher modifies the test by inserting a set of very easy problems among the standardized questions, and gives the modified test to a sample of n=36 students.  If the average test score for the sample is M=104.  is the result sufficient to conclude that inserting the easy questions improved student performance? Use a one-tailed test with ox.01