The domain is all real numbers, and the range is \( y \leq 0 \). The domain is \( x>0 \), and the range is all real numbers. The domain and range are all real numbers. The domain is \( x<0 \), and the range is \( y>0 \).

The scenario you've described can refer to different types of functions or graphs, but if we look closely, it seems like we might be dealing with polynomial functions and their properties! For instance, a function with a range of \( y \leq 0 \) could be a downward-opening parabola, such as \( f(x) = -x^2 \). Such a function has its peak at the vertex, where it touches a maximum point before it declines indefinitely. On the flip side, a function that has the range as all real numbers could be something like \( f(x) = \tan(x) \) for \( x > 0 \). This trigonometric function oscillates wildly and covers all y-values through its periodic nature while also being undefined at specific intervals. Understanding these properties helps us not only analyze functions better but also visualize how they behave in different contexts!