2.15000-500-300 =14200 1500+300 = 15800. This is the profit price range.
The topic asks the trader, that is, the buyer, not the investor. 15900-15000-500 = 400 points; 400-300= 100, so the trader's income 100.
I hope I can help you. I think you just didn't see the topic clearly.
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