If the half-life of uranium-235 is 704,000,000 years and 12.5 g of uranium-235 remains after 4,560,000,000 years, how much of the radioactive isotope was in the original sample?

Which elements are found in glucose, the product of photosynthesis? a. carbon, hydrogen, and oxygen b. carbon and hydrogen c. carbon, nitrogen, and oxygen d. hydrogen, nitrogen, and carbon