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

### Instruction:
James takes 20 units per semester at community college.  If each unit costs $50 how much does he pay for 2 semesters?

### Response:
 เขาจ่าย 50*20=$<<50*20=1000>>1000 ต่อภาคเรียน
ดังนั้นเขาจะต้องจ่าย 1000*2=$<<1000*2=2000>>2000