Notice that:
1.- The number of viewers in millions of show A can be computed using the following expression

which is not a linear equation.
2.- The number of viewers of show B can be computed using the following expression:

which is a linear expression.
Now, after 6 years, show A will have:

millions of viewers and show B will have

viewers.
Answer:
The function for Show A is nonlinear.
The function for Show B is linear.
Show B will have more viewers.