5. Canadian unionization rates are about three times as large as unionization rates in the Unites States (U.S.). One potential hypothesized explanation is that there is greater opposition to unions by U.S. employers/firms than by Canadian employers. Campolieti et all., in a 2013 Journal of Labor Research paper discussed in class, study this issue. With reference to this study: (a) what was the data source used in the study (b) what were the main issues that the study tried to address or answer ((2) what were the key findings and conclusions of the study