a. Mexico has increased cereal production through both intensification and expansion. During the Green Revolution, Mexico became a testing ground for new high-yielding varieties of maize, wheat, and rice. These new varieties, along with the use of fertilizers and pesticides, helped increase yields and allow for multiple harvests per year. Additionally, there has been expansion of agricultural land, particularly in the north of the country, where large-scale irrigation projects were undertaken to transform arid lands into productive agricultural areas.
b. While Mexico's cereal production has increased significantly since the Green Revolution, it has not always been sufficient to support the country's population growth. In the years following the Green Revolution, Mexico became a major exporter of wheat and maize. However, in recent decades, population growth has outpaced agricultural production, leading to increased reliance on food imports. In particular, Mexico has become heavily dependent on imports of yellow corn, which is used as animal feed and a key ingredient in many processed foods.