Andrey works at a call center, selling insurance over the phone. While debating over which greeting he should use when calling potential customers - “Howdy!” or “Hiya!” - he decided to conduct a small study. For his subsequent $500$ calls, he chose one of the greetings randomly by flipping a coin. Then, he compared the percentage of calls he succeeded in selling insurance using each greeting. **What type of a statistical study did Andrey use?** [[☃ radio 1]] Andrey found that the success rate of the conversation that started with “Howdy!” was $20$ percent greater than the success rate of the conversation that started with “Hiya!” Based on some re-randomization simulations, he concluded that the result is significant and not due to the randomization of the calls. **What valid conclusions can be made from this result?** Mark the most suitable choice. [[☃ radio 2]]