From previous experience, the owner of an apple orchard knows that the mean weight of gala apples is 140 grams. This year there has been more precipitation than usual and the owner believes the weights of the apples are heavier than usual. The owner takes a random sample of 30 apples and records their weights. What type of sampling is described in this study?
The owner randomly selects one group of 30 apples and records their weights, so the study uses one sample. The historical mean of 140 grams is a reference value, not a second sample of apples. Therefore, the correct choice is C, one sample.
AI-written and checked against the verified answer.