All you have to remember is that is the order at LEAST n.

When you look at it this way, here is a good list to know, in order from smallest to largest rate of growth:

(c is some constant)

(logarithmic)

(linear)

(logarithmic)

.

.

.

.

.

.

If you are looking for the LEAST order, you look for the smallest in this list and that entire function takes that order.

If you are looking for the HIGHEST order, you look for the largest in this list and that entire function takes that order.

I'm sure you can get through this now.