A store manager wishes to investigate whether there is a relationship between the type of promotion offered and E number of customers who spend more than $30 on a purchase. Data will be gathered and placed into the two-wa table below. Customer Spending by Promotion Run Customers Spending More than $30 Customers Spending $30 or Less $10 off $50 15% off $5 off $25 Buy-1-Get-1 Half Off Which statement best describes how the manager can check if there is an association between the two variables O The manager must check relative frequencies by row because there are more than two different promotions. The manager must check relative frequencies by column because there are more than two different promotion​