The graph of a line and an exponential can intersect twice, once, or not at all. Describe the possible number of intersections for each of the following pairs of graphs. Your solution to each part should include all of the possibilities and a quickly sketched example of each one.

1. A line and a parabola

2. Two different parabolas

3. A parabola and a circle

4. A parabola and the hyperbola $y =\frac { 1 } { x }$