An experimental bumper was designed to reduce damage in lowspeed collisions. This bumper was installed on an experimental group of vans in a large fleet, but not on a control group. At the end ofa trial period, there were 12 repair incidents (a "repair incident" is an accident that resulted in a repair invoice) for the experimental group and 9 repair incidents for the control group. The dollar cost per repair incident is shown below. 01d bumper: 1,874, 2,173, 2,182, 1,644, 2,464, 834, 1,685, 1,840, 1.086 New bumper: 549, 1,625, 2,065, 1,403, 1,348, 1,331, 884, 936, 2,219, 2,049, 1,900, 1,843 Click here for the Excel Data File (a) Perform a twotailed Mann-Whitney test at a = .05 and find the zstatistic and pvalue. (Use the formulas in the textbook to determine the z-statistic and use Excel to calculate the p-value. If you use MegaStat to check your answers, you must use version 10.2 Release 2.1 or higher and do NOT correct for ties or continuity (leave boxes unchecked). Round your z-statistic to 3 decimal places and p-value to 4 decimal places.) 0 Answer is complete but not entirely correct. z-statistic -0.640 6 p-value 0.5224 9