61 for every standard cd player, so, sales is:
61s
66 for every portable cd player, so, sales is:
66p
At least $405 means 405 or more, we can represent this as:

By making "s" be the x-axis and "p" be the y-axis, we can graph this line.
Since it's an inequality that is greater than or equal to, we shade the region "above" the line.
Shown below: