12.5%, every 500 years you take away half of the substance (50%) -> 25% -> 12.5%
you divide your number 3 times because 1500/500=3
Answer:



You can group the addends in any combination and it won't change the result.
Answer:
A
Step-by-step explanation:
Y= -35
Y = -1
I put the work in the picture below!
(Hint: just substitute the x for its number and do simple adding and subtracting)