Just use derivatives:
f'(x)= .48x-.96 = 0, x = 2, since the coeff of x^2 is +, this is a minimum
x=0 1989, so x = 2 is 1991! :)
Answer:

Step-by-step explanation:
I am going to assume that by "f-1(x)" you mean
, which makes this an inverse function problem. To find the inverse of a function, simply swap x and y, then solve for y.

Answer:
it would be b
Step-by-step explanation: