The first question, just one part needs to be adjusted, that is to say, the probability that one part is adjusted, the other two parts are not adjusted, and the three parts are not adjusted is 0.9, 0.8 and 0.7 respectively; That is the probability that a component needs to be sorted out: 0.1* 0.8 * 0.7+0.9 * 0.2 * 0.7+0.9 * 0.8 * 0.3 = 0.398. Second question: at least two components need to be adjusted, including two components and three components. Two components need to be adjusted, that is, two components need to be adjusted and one does not need to be adjusted. The probability of two adjustments is 0.1* 0.2 * 0.7+0.1* 0.8 * 0.3+0.9 * 0.2 * 0.3 = 0.092, and the probability of three adjustments is 0.1* 0.2 * 0.3 =