A study investigated whether regular mammograms resulted in fewer deaths from breast cancer over a period of 19 years. Among 30,635 women who never had mammograms, 184 died of breast cancer, while only 141 of 30,245 who had undergone screening died of breast cancer. a) Do these results suggest that mammograms may be an effective screening tool to reduce breast cancer deaths? b) If your conclusion is incorrect, which type of error did you commit? HA P1 P2 =0 Determine the test statistic. z= (Round to two decimal places as needed.) HA: P1 - P20