What is the radius of a circle with circumference 94.2 mm?

    c = 2πr
94.2 = 2(3.14)(r)
94.2 = 2(3.14r)
94.2 = 6.28r
6.28     6.28
      15 = r

Your answer  would be  r =  14.99  mm 

To tell if it is an even function

replace all x with -x and if you get the same equaiton simplified, then it is even

g(-x)=(-x-1)^2+1
g(-x)=x^2+2x+2
original
g(x)=x^2-2x+2
not same
not even

g(-x)=2(-x)^2+1
g(-x)=2(x^2)+1
g(-x)=2x^2+1
original
g(x)=2x^2+1
same
it's even

g(-x)=4(-x)+2
g(-x)=-4x+2
original was
g(x)=4x+2
not same
not even

g(-x)=2(-x)
g(-x)=-2x
original
g(x)=2x
not same
not even

the only one that is even is
2nd one
g(x)=2x^2+1

-x-1)(-x-1