Charles Keeling’s work at the National Oceanic and Atmospheric Administration (NOAA) Mauna Loa Observatory paved the way to understanding how human activities can lead to global warming. Which greenhouse gas did Charles Keeling measure at the observatory?
A)carbon monoxide
B)methane
C)nitrous oxide
D)carbon dioxide

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the principle of segregation describes how pairs of gene variants are separated into reproductive cells. from his data, mendel formulated the principle of segregation. we now know that the segregation of genes occurs during meiosis in eukaryotes, which is a process that produces reproductive cells called gametes.