How to tackle growth rate order question?

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How do I tackle these kind of growth rate questions? I almost always somehow rank them wrongly...

Refer to screenshots: Q1 Q2

My current approach:

I have a list of general orders: 1 < log n < sqroot(n) < n < n log n , n^2 < n^3 < ... < 2^n < 3^n < ... n^n

I then try to convert those in the question to the format above and then order them accordingly.

However, I find that I sometimes still order them wrongly, although some of them are still in the correct order

Another way I tried was to substitute the n with a fixed value e.g. '99' and then order them accordingly to the resulting output - it seemed to work but I am not sure if this will always work?

What is the best way to do this? Would me substituting the n with a 'large' value e.g 99 always work, or when will there be cases that will fail?