Ask a question of a company through email and you have about a fifty-fifty chance of getting a full correct answer. That’s the findings of a study just released by STELLAService, the provider of customer service ratings for online retailers. Mystery shoppers sent more than a thousand emails to 25 of the largest retailers asking two simple questions, like do you have a particular shoe in red and in a size six. STELLAService reports LLBean.com was the most dependable, answering 88.9 % of customer emails completely. Gap.com did well answering the questions 84% of the time and rounding out the top three is Zappos.com with a 75% correct and complete response rate. Researchers say the best way to get a response is to be specific in the subject line and include your order confirmation number, if available.