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

### Instruction:
Without factoring in the cost of depreciation for his car John made $30,000 doing Uber.  When he finally traded in the car he bought for $18,000 he got $6000 back.  What was his profit from driving Uber?

### Response:
 รถของเขาค่าเสื่อมราคา 18,000 - 6,000 = <<18000-6000=12000>>12,000 ดอลลาร์
ดังนั้นเขาได้กำไร 30,000 - 12,000 = <<30000-12000=18000>>18,000 ดอลลาร์