divisibility - The method of solving for a factor of $90!$

If $90! = (90)(89)(88)...(2)(1)$, then what is the exponent of the highest power of $2$ which will divide $90!$ ?

How would I apply one of the easiest method from Here?

I need help on applying the link to this question.

I do not understand which one explains my case, and how I can solve using the method.

I would appreciate if someone showed how it is applied to this