At Hogwarts School of Witchcraft and Wizardry, Professor Snape was concerned about grade inflation, and suggested that the school should issue standardized grades (or z-scores), in addition to the regular grades. How might this work? Harry was in four classes, each with 20 students. Harry’s score, the class mean, and the class standard deviation are given below. Compute his standardized grade in each class. If we judged by standardized grades, where did he do best? Round your answer to 2 decimal places.