The mass of a proton is approximately 1.67 x 10−24, and the mass of an electron is approximately 9.11 x 10−28.what is the approximate ratio of the mass of the proton to the mass of the electron?

What’s the ratio in simplest form if you count 14 robins out of 150 birds

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?

How do i do this? i don’t understand