Answer:
c
Step-by-step explanation:
f(x)=x^2+12x+26
Vertex form of f(x) = a(x-h)^2 +k
We change f(x) into vertex form using completing the square method

We take half of square of middle term
middle term is 12
Half of square of 12 is
then 6^2 = 36
Add and subtract 36 to complete the square


The vertex form 
Answer:
It is m(x) = 20,000(0.97)^x.
Step-by-step explanation:
After 1990, each year has (100-3) = 97% ( or 0.97) of visitors that it had the previous year.
So m(x) = 20,000(0.97)^x (answer).