The answer to #1 is A and C.
When a function is reflected across the line y=x, the resulting function has the following property:
For a point on the function (a,b), the reflected function has a point (b,a).
This is true for the two functions,
This is also the definition of an inverse.
Answer to #2 is "vertical stretch by a factor of four"
The function is stretched vertically upward at every point by a factor of four, meaning that at every point, the new function is 4*f(x)