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

### Instruction:
John gave his fiancee a $4000 ring on their engagement day, a $2000 car as a gift on their wedding day, and a diamond brace twice as expensive as the ring he gave her during the engagement. What's the worth of the presents John gave to her fiancee?

### Response:
 มูลค่าของของขวัญทั้งหมดคือ 4000 + 2000 + 2 x 4000 = 12000 ดอลลาร์