900,000 because it is rounded up because of how rounding works
The answer is 24.5. Just plug the numbers in
Its an exponential growth
The perimeter is just all the lines around the outside of the shape so basically take all the numbers and add them together to get the answer
If your original equation was 
, then a reflection over the x-axis means you need all the y-values to switch sign. This means you need to multiply that function by -1.
or 
