Gold-198 is used to treat liver cancer. Its half-life is 2.7 days. If you ingest 3.75 mg of Au-198, how long would you have to wait for the amount of Au-198 to fall to 0.75 mg?

aquifers are bounded above and below by impermeable rock. the driving force of groundwater movement in confined aquifers is pressure, rather than gravity.

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.

the pseudoscience are like beliefs, theories, or like practices that are considered scientific