Problems

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One day a strange notebook was found on the stairs. It contained one hundred statements:

“There is exactly one incorrect statement in this notebook”;

“There are exactly two incorrect statements in this notebook”;

“There are exactly three incorrect statements in this notebook”;

...

“There are exactly one hundred incorrect statements in this notebook.”

Are any of these statements true, and if so, which ones?

What word is encrypted: 22212221265121? Each letter is replaced by its number in the English alphabet.

Can the following equality be true: \[K \times O \times T = A \times B \times C \times D \times E \times F\] if you substitute the letters with the numbers from 1 to 9? Different letters correspond to different numbers.

An entire set of dominoes, except for 0-0, was laid out as shown in the figure. Different letters correspond to different numbers, the same – the same. The sum of the points in each line is 24. Try to restore the numbers.

Before you is a lock “with a secret” (see the picture).

If you put the arrows on the desired letters, you will get the keyword and the lock will open. What is this word?