The acceleration is defined as the ratio between the change in velocity and the time elapsed to perform such a change.
These "changes" are indicated with the capital greek letter delta,
, and when you write
you mean the difference between the finial and the inital values of the variable x:

So, the acceleration is defined as

In this case, the initial velocity is 35, the final velocity is 65. Assuming we start the clock at the beginning of the observation, the inital time is 0 and the final time is 5. So, we have
m/s^2
Answer:
2,000,000
Step-by-step explanation:
Simple maths, really.
65 times 2 is 130, and the population is already 500,000 with no time passing. 65 years later, the population would be 1,000,000. 65 years after that, the population would double again, so the answer would be 2 million.
Hope this helped!
X will equal 12, and y will equal 18.