Below is an instruction that describes a task. Write a response that appropriately completes the request in Thai. Please answer in Thai.

### Instruction:
Alexa has a lemonade stand where she sells lemonade for $2 for one cup. If she spent $20 on ingredients, how many cups of lemonade does she need to sell to make a profit of $80?

### Response:
 เพื่อทำกำไร 80 เหรียญ เธอต้องทำรายได้ 80 + 20 = 100 เหรียญ
เธอต้องขายน้ำมะนาว 100 / 2 = 50 แก้ว