Words beginning with 'ar'

How many words could one make using the combination specified?
In total, there are up to 2,546 words.

What is the most common word that starts with 'ar' in the dictionary?
When it comes to well-known words, there's 'are' which is the 37^th most common word.

How many characters are in the longest word from this list?
'Archaeopterygiformes'

What is the highest scoring word you can play in Scrabble ?
With a vast 2,546 entries, you may want to pick 'araquaju' which scores 24 points.

Is there a specific word from this page which could be considered as interesting?
Our favorite interesting word from this page is 'archebiosis'. The definition of 'archebiosis' is as follows: "To origination of living matter from non-living. See Abiogenesis. Bastian.". Source Oxford Dictionary.