Words that include 'usu'

Which word on this page ranks as the most common?
The most common word is 'usual', which is in fact the 939^th most common word in the dictionary.

What's the max number of words you are able to put together using this list?
Overall, there are 117 words.

Is there an example word from this page of word with 'usu' in them which could be thought of as unusual in any regard?
Undeniably one of the most strange words from this list of words with 'usu' in them is 'usury'. 'Usury' is defined as "1. A premium or increase paid, or stipulated to be paid, for a loan, as of money; interest. [Obs. Or Archaic] Thou shalt not lend upon usury to thy brother; usury of money, usury of victuals, usury of anything that is lent upon usury. Deut. Xxiii. 19. Thou oughtest therefore...", according to the dictionary.

How many characters are in the longest word on this page?
The largest word located by Dictionarypedia is 'deorusumduction'.

In Scrabble, what's the highest number of points possible using this list of words containing 'usu'?
As there are plenty of words to pick from, you may want to go for 'busulfan' which scores 13 points.