【判断题】In testing a hypothesis, statements for the null and alternative hypotheses, as well as the selection of the level of significance, should precede the collection and examination of the data.
【判断题】The main problem of calculating the total index by the weighted aggregative index is the selection of the same measurement factors and the determination of the period.
【单选题】听力原文: In Mexico, Yucatan State Governor Yvonne Ortega celebrated the selection of the Chichen Itza pyramid. Ortega said, 'the Mayans brought luck to us, the people from Yucatan, but now we must take a...