Suppose you will conduct an experiment on whether short breaks improve call center operators' performance throughout the day. You know that a call center operator, on average, signs up 12 customers with a standard deviation of 2 in the population of company employees for a given company. How many customers would operators in the research sample have to sign on to have a small effect size? 0.80(2)+ 12 0.50(2) + 12 0.10(2) + 12 0.30(2) + 12