If in the given word VITREOUS all the constants are first arranged alphabetically, and then all the vowels are arranged alphabetically, which letter will be second to the right of fourth from the left?

The given word is VITREOUS. Of which , TRSV are the consonants and IEOU are the vowels. Now, after making the changes as given in the question  we get following arrangment: RSTVEIOU.

Again from precalculation, we know that second to the right of fourth  from the left means (2+4=) 6th from the left. i.e I