Element X is a radioactive isotope such that every 27 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 7900 grams, how much of the element would remain after 12 years, to the nearest whole number?

use an equation of ratios to determine the amount of gas needed to fill the tank.

    0.2             0.8

  =    

288.75             x

                                                              231 gal

so, 0.2x = (0.8)(288.75 gal), and x = = 1155 gal.

                                                                0.2

it would take 1155 gal. to fill the tank.

the cost would be

1155 gal         $3

* = $3465   (answer)

      1           1 gal

hope this you

use google you idiot omg you're so annoying

step-by-step explanation: