Which of these tables could represent a quadratic function?
a.
x y
1 -1
2 4
0 -4
-1 -7
-2 -10
b.
x y
-5 -3
-3 5
-1 5
1 -3
2 -10
c.
x y
2 4
2 2
2 0
2 -2
2 -5
d.
x y
-6 4
-5 -4
0 -4
4 -4
5 -4

The population of a small rural town in the year 2006 was 2,459. the population can be modeled by the function below, where f(x residents and t is the number of years elapsed since 2006. f(t) = 2,459(0.92)