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

### Instruction:
James pays $1000 for advertising.  It brought 100 customers to his site and 80% of those bought something at the store that cost $25.  How much profit does he gain from the ad?

### Response:
 100 * 0.8 = <<100*.8=80>>80 ลูกค้าซื้อสินค้า
นั่นหมายความว่าพวกเขามีค่า 80 * 25 = $<<80*25=2000>>2000
ดังนั้นเขาได้กำไร 2000 - 1000 = $<<2000-1000=1000>>1000 จากการโฆษณา