In a small town, a group of friends decided to fundraise for a local charity by selling handmade crafts. They can make c crafts per hour, and they plan to work for a total of h hours. The total number of crafts produced after h hours can be represented by the equation:
$$N = c \cdot h$$
They estimate that each craft can be sold for $5. If they want to raise a minimum of $500 for the charity, what inequality must hold true for the number of crafts made?