Kelly sells magazine subscriptions after work. The half year subscriptions cost $12, and the full-year subscriptions cost $20. Today, Kelly has 20 subscriptions cards with her, only one subscription can be ordered on each card, and she wants to sell subscriptions totaling at least $300. If the solution region represents the amount of half-year and full-year magazine subscriptions Kelly needs to sell to reach her goal, which graphs shaded area represents the solution? region?
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