1. **State the problem:** The Read and Feed restaurant surveyed 150 customers who chose to answer an online survey printed on receipts. 60% of these respondents said they were satisfied with the service. We need to determine which conclusion about the customer population is valid based on this data. 2. **Understand the data:** - Sample size: 150 customers who chose to answer the survey. - Sample satisfaction rate: 60%. 3. **Important rule:** A sample must be representative of the entire population to generalize results. Here, only customers who chose to answer the survey (and presumably have internet access) are included, which may introduce bias. 4. **Analyze each conclusion:** - A: "60% of customers in this sample are satisfied, but we cannot conclude anything about the population." - This is true because the sample is self-selected and may not represent all customers. - B: "About 60% of all Read and Feed customers are satisfied." - This is not necessarily true because the sample may not represent all customers (e.g., those without internet access or who did not respond). - C: "About 60% of all Read and Feed customers who have internet access are satisfied." - This is more reasonable since the survey was online, so the sample represents customers with internet access who chose to respond. 5. **Final conclusion:** The valid conclusion is C. **Answer:** C