If h(x) = f(–x), this is saying that your graph will be reflected over the y-axis. In other words, the x-values of every point on the graph of y=f(x) will be switched to the opposite sign. The graph will be flipped over sideways.
For example, if (1,-4) is a point on y=f(x), then y=h(x) will have (–1,-4) on it.
If h(x) = –f(x), this is saying that your graph will be reflected over the x-axis. In other words, the y-values of every point on the graph of y=f(x) will be switched to the opposite sign. The graph will be flipped upside-down.
For example, if (1,–4) is a point on y=f(x), then y=h(x) will have (1,4) on it.
While you are given the equation for f(x) in each exercise, the function f(x) does not impact the transformation at all. What is said above is true for all functions.
If you want to graph them, then for 4:
f(x) = -3 - x
h(x) = f(-x) = -3 + x
For #5:
f(x) = 1/3 x + 1
h(x) = -f(x) = -1/3 x - 1