Student A is an American who imports rubber from South East Asia. He used to import from Thailand but recently he has been buying cheaper rubber from Malaysia. In fact, he has a ship waiting to go back to America (the ship is only half full) so he has called into Thailand to negotiate a better price for Thai rubber. Student A only imports rubber and he is in Thailand to get a better price.
Americans eat lots of bread (it is a staple food) and this summer they only have a small amount of wheat (wheat is used to make bread). However, there are many Asian restaurants in America and they all need rice and there is a shortage of bread.