Answer:
226 grams
Step-by-step explanation:
This will be an exponential function. The formula for exponential functions and half life is A=Ao * (1/2)^(t/h)
A stands for final amount, Ao for initial amount, 1/2 is the decaying factor (after a half life, one mg becomes 1/2 mg), t stands for time, and h is the half life.
To solve your problem, the equation would be A=904 * (1/2)^(70/35)
The parentheses are necessary for your calculator or else you will get the wrong answer.