harperharmony123 harperharmony123 17-10-2022 Mathematics Answered Classwork Twelve students were given an arithmetic test, and the times (in minutes) to complete it were 10, 9, 12, 11, 8,15, 9, 7, 8, 6, 12, and 10. Find: a) The range b) Variance and c) Standard deviation by using all the values of the data set.