Find f(a) if f(t)=t^2-2t-2

The administrator of a large assisted living facility wanted to know the average age of the residents living at the facility. he randomly selected 12 residents and determined their age, listed here: 80, 65, 75, 83, 68, 73, 88, 79, 94, 72, 79, 68 what's the average age of the sample of residents? a. 79 years old b. 68 years old c. 75 years old d. 77 years old

Ineed to know the answer to this algebra question.

Solve each quadratic equation by factoring and using the zero product property. [tex]x^2+6x+8=0[/tex]