The table below brings the time spent (in minutes) on the graded practice exam 1 and the scores of 10 randomly selected ECN 221 online students. time spent (in mins) Grade (out of 10) 36 5 30 31 2 39 6 22 6 28 8 32 6 24 9 27 8 8 9 Calculate the Z score for the time spent when time is equal to 45 minutes. Use variance = 135.73 Use four decimal places, and include the zero before the decimal place or the MINUS sign when needed. E.g., -0.1234. No credit will be given for rounding mistakes