I need help organizing a surprise birthday party for my friend. The party will be held at [location] and I expect around [number_of_guests] guests. Can you provide some tips on decorations, food, and activities? Please include at least 3 placeholders such as [location] and [number_of_guests]. Also, highlight at least 2 sections in your answer using markdown. Finish your response with the exact phrase "Let's make this birthday unforgettable."

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