Final answer:
The exchange rate between the Thai baht and the dollar has changed, causing the dollar to weaken relative to the baht.
Step-by-step explanation:
The exchange rate represents the value of one currency in terms of another currency. In this case, the exchange rate has changed from 40 Thai baht per dollar to 35 Thai baht per dollar. This means that the value of the Thai baht has increased relative to the dollar.
For example, if you had 100 dollars before the exchange rate change, you would have received 4,000 Thai baht. After the exchange rate change, you would receive 3,500 Thai baht for the same 100 dollars.
Therefore, the dollar has depreciated or weakened in relation to the Thai baht.