Let \( c \) be the function that gives the average cost per book in dollars when using an online store to print \( x \) copies of a self-published paperback book. The function is given by:

\[ c(x) = \frac{120 + 4x}{x} \]

1. What is the approximate cost per book when 50 books are printed? When 100 books are printed?

2. The author wants to charge $8 per book. About how many should be printed to make a profit?

3. What is the value of \( c(x) \) when \( x = \frac{1}{2} \)? How does this relate to the context?

4. What does the end behavior of the function say about the context?