A study was designed to investigate the effects of two variables - (1) a student's level of mathematical anxiety and (2) teaching method - on a student's achievement in a mathematics course. Students who had a low level of mathematical anxiety were taught using the traditional expository method. These students obtained a mean score of 380 with a standard deviation of 20 on a standardized test. Assuming a bell-shaped distribution, where would approximately 95% of the students score?
◦ between 340 and 420
◦ below 340 or above 420
◦ between 320 and 440
◦ below 320 or above 440