{"text_format":"2","workbook":"xls","n_sheets":3,"sheets":["Sheet1","Sheet2","Sheet3"],"not_rendered":{"charts":0,"images":0,"macros":0,"external_links":0,"defined_names":0,"comments":0,"pivot_tables":0},"unopened":[],"bounds":{"document_bytes":16777216,"sheet_cells":100000,"run_cost":"one","rows_first":2000,"rows_last":500,"rows_between":2000,"halvings":0,"cell_chars":16384,"cell_head_chars":4096},"cells_cut":0,"cells_raw":0,"read":"whole","date_system":"1904","formulas":"cached_only"}

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["Parent (Radioactive) Isotope",null,"Daughter (Radiogenic) Isotope",null,"Half-life (t1/2)","Half-life (scientific notation)"]
["Carbon-14","14C","Nitrogen-14","14N","5730 years","5.73 x 103 years"]
["Beryillium-10","10Be","Boron-10","10B","1.5 million years","1.5  x 106 years"]
["Uranium-235","235U","Lead-207","207Pb","704 million years","7.04 x 108 years"]
["Uranium-238","238U","Lead-206","206Pb","4400 million years","4.4 x 109 years"]
["Potassium-40","40K","Argon-40","40Ar","11930 million years","1.193 x 1010 years"]
["Thorium-232","232Th","Lead-208","208Pb","14010 million years","1.401 x 1010 years"]
["Lutecium-176","176Lu","Halfnium-176","176Hf","35700 million years","1.57 x 1010 years"]
["Rhenium-187","187Re","Osmium-187","187Os","42300 million years","4.23 x 1010 years"]
["Rubidium-87","87Rb","Stronitium-87","87Sr","48800 million years","4.88 x 1010 years"]
["Samarium-147","147Sm","Neodymium -143","143Nd","106000 million years","1.06 x 1011 years"]
[{"$nulls":5},"(all half-lives from Dickin, 1995)"]

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