Answer:
Chemicals used to increase crop growth: fertilizers
Chemicals used to prevent insect infestation of crops: pesticides
Choosing the single most efficient crop variety for the exisiting conditions: monoculture
Planting different crops each year for healthier fields: crop rotation
Explanation:
The Earth has been around for approximately 4.6 billions of years. Humans first evolved from I believe apes around 5 million years ago, with Homo Sapiens evolving around 2 million years ago or so. The current calendar system we use today, the Gregorian system (in most western nations like America) marks the year 0 as the year Jesus Christ was born, not when the Earth was formed. Years before Jesus' birth are marked as B.C., with the numbers getting higher the earlier you go. In the Japanese system, the year is marked by how long the current Emperor has been in power, making the current year (2017) Heisei 29 in traditional Japanese calendars.
Geography is important because it helps us understand the plants movement changes and systems
Answer: Glacier
Definition:
a slowly moving mass or river of ice formed by the accumulation and compaction of snow on mountains or near the poles.
Rivers, because it has a constant flow from other water sources so that means it could just flow right in