Answer:
a right
Step-by-step explanation:
Since you're looking for the unit rate, you can start do this:

And yes,

is also correct, it's just switching around the 15
(-y + 5a - 4) + (3y - a - 5) is simplified to 2y + 4a - 11
Answer:
25%
Step-by-step explanation:
% Change = Change ÷ Original × 100
% Change = 19 ÷ 76 × 100
% Change = .25 × 100
% Change = 25
At death means x= 0, so on the graph you can see that (0, 500), so 500 carbon atoms are present at death.
Plug 11,240 in for t in the equation, and you are left with N(t) = 500(1/2)^2 = 125 carbon atoms.
See the graph point (25,000, 24.298)? That means that after 25,000 years 24.298 carbon atoms will be present. So the answer is 25,000 years.