1. Increases in the world's population means that we need more food to feed the larger population. Explain the link between a larger population and the world grain markets. Illustrate and explain the likely impact on the prices and quantity of grain exchanged ? 2. The need for more housing and the attraction of cities means that urban areas encroaching adjacent farm areas. Land used in cultivation of grain is declining. Illustrate and explain the likely impact of this decline in land cultivation on the price and quantity of grain exchanged