Extemporines or Extemporiness: How To spell?

The word Extemporines is misspelled against Extemporiness, a noun meaning "The quality of being done or devised extempore"

Extemporiness has double 'ss' in the end mispronounced as 's'
Remember double 'SS' appears in the end of this word which should not be misspelled with single 'S'
Wrong Spelling:  extemporine-s 
Correct Spelling:  extemporine-ss 
Find more incorrect spellings of Extemporiness to spell right way.

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