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Bismuth-210 is an isotope that radioactively decays by about 13% each day, meaning 13% of the remaining bismuth-210 transforms into another atom (polonium-210 in this case) each day. if you begin with 233 mg of bismuth-210, how much remains after 8 days?

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup

Write the expression 7x^3-28xy^2 as the product of 3 factors