How many passwords can we generate of lengths from 1 to 5 if we have 27 symbols数值题

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Question text A school is setting up activity packages that include a combination of books and puzzles.There are 4 different books and 3 different puzzles available. Student 1:"I was asked to calculate how many packages can include 1 book and 1 puzzle. I used the multiplicative principle: 4 × 3 = 12."Answer 1 Question 45[select: , The student is incorrect; the additive principle should have been used and the correct result is 7., The student is correct; the multiplicative principle applies and the result is 12., The student is incorrect; combinations should have been used and the total is 6.] Student 2:"I was asked to calculate how many packages can be made with just 1 item (either a book or a puzzle). I used 4 × 3 = 12."Answer 2 Question 45[select: , The student is correct; the multiplicative principle gives 12, which is accurate., The student is incorrect; combinations apply here and the answer is 6., The student is incorrect; the additive principle should be used here. The correct total is 7.] Student 3:"I was asked to calculate how many packages can include 2 books and 1 puzzle. I did C(4,2) × C(3,1) = 6 × 3 = 20."Answer 3 Question 45[select: , The student is incorrect; the combinations are correct but the total was evaluated incorrectly. The correct result is 18., The student is correct; combinations and multiplication give 20., The student is incorrect; permutation should have been used, and the correct value is 24.]

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