240 days is 4 times the half-life, which means that a sample of 1000 mg will decay to

after 240 days.
$310 dollars because after it res and decreased it gained $.10 and 100 x 3 is 300 so thats before you calculate how much it rose so .10 x 100 is 10 so add that to 300 and you get 310
Step-by-step explanation:

Well, they're both divisible by 2 (24 ÷ 2 = 12) (90 ÷ 2 = 45)