Answer:
The mean is 4.
Step-by-step explanation:
Mean simply means average. To do so, just add up all the numbers and divide by the amount of numbers present.
2 + 5 + 5 + 6 + 7 + 1 + 2 = 28/7 = 4
g(5) means we substitute every x in the equation with a 5.
g(5) = (5)^2 - 4.
g(5) = 21.