1. Arrange the natural numbers from 1 to 101 in a row so that the difference between any two adjacent numbers is equal to 2 or 5.
Answer: $101,99,97, \ldots, 9,4,2,7,5,3,1,6,8,10, \ldots, 100$.

Remark. Other examples are possible.

Criteria. If the solution is incorrect - 0 points.

If any correct example is provided - 7 points.

If the reasoning is correct but there is a computational error - 3 points. If the solution is correct - 7 points.