1.Growing more crops on less farmland.
2.Because he had a good rice harvest after planting the super hybrid rice invented by Professor Yuan.
3.The hybrid rice Professor Yuan Longping invented tastes very nice.
4.In 2010.看见玻璃瓶里的蚂蚁都死了,“我”和妹妹得出的结论是:药瓶不透气而导致蚂蚁的死亡.
后来又想出什么办法:因在火柴盒上扎了一些小眼,蚂蚁们又不愿被关起来都逃跑了.