Answer:
37.5g
Explanation:
The half-life is the time taken for a radioactive substance to decay to half its original composition;
Original composition here is = 4800g of U-238
How many grams remain after 7 half-lives;
After each life, the uranium reduces by half;
Amount remaining = 4800 x
= 37.5g
After 7 half lives, 37.5g of the original sample will remain.