what does "one of which"indicate to?
[Two men were responsible for the American and Presidential flags and the Presidential seals, one of which I had to be correctly mounted before every Kennedy speech. ]

what does "one of which"indicate to? what exactly shoule be mounted before the presiden'ts speech?one of American flag and Presidential flag? or both?

Question

what does "one of which"indicate to?
[Two men were responsible for the American and Presidential flags and the Presidential seals, one of which I had to be correctly mounted before every Kennedy speech. ]

what does "one of which"indicate to? what exactly shoule be mounted before the presiden'ts speech?one of  American flag and Presidential flag? or both?

Answer

one of which = either the flag or the seal
It does not state exactly which one. But I would presume it's the flag. You don't mount a seal.