Question 6 1 pts To test the effectiveness of a business schooi preparation course. 8 students took a general business test before and after the course. The results are in the accompanying table. The difference scores reect the results of the exam after the course minus the results of the exam before the course. Student Exam Score Before Course Exam Score After Course 1 530 670 2 690 770 3 910 1,000 4 700 710 5 450 550 6 320 870 7 320 770 8 63D 6 10 The sample mean of difference I dBar J is 50. and the sampie variance of the difference scores 52d is 4223.571. What is the value of the standard error of the mean difference {SEldBar]}? Round to the nearest thousandth. Note: 5d = is} and SE[ dBar ) = i v