"100640843"@en-us . "carbon dating"@en-us . . . . "0"^^ . "a chemical analysis used to determine the age of organic materials based on their content of the radioisotope carbon-14; believed to be reliable up to 40,000 years"@en-us . . . "0.125"^^ . "radiocarbon dating"@en-us . . . . . "carbon-14 dating"@en-us . "00992732-n"^^ . "100934915"@en-us . . "100992732"^^ . "radiocarbon dating"^^ . . .