Riddle – we are one inside of one inside of one inside of one inside of one. what are we?

Aresearcher proposes to conduct a study at a foreign site. the research has been determined to be exempt from the federal regulations by institutional policy. according to federal regulations, is review required at the foreign site? if a proposed study qualifies for exemption, federal regulations do not require review at the foreign site where it will be conducted but still require review at the u. s. site by the institution’s irb. if a proposed study qualifies for exemption, federal regulations do not require review at the foreign site where it will be conducted. if a proposed study qualifies for exemption, federal regulations do require review at the foreign site where it will be conducted. if a proposed study qualifies for exemption, federal regulations do not require review at the foreign site where it will be conducted, but still require review by the institutional official at the local site.

Newspaper started by john campbell:

Which us president proposed a decimal based measurement system for the us