Final answer:
Mathematics is used in the Farmers' Almanac to calculate forecasts using astronomical information and mathematical formulas.
Step-by-step explanation:
The subject of the question is Mathematics.
Mathematics is used in the development of mathematical formulas and calculations to calculate forecasts in the Farmers' Almanac. These mathematical formulas help predict long-range weather patterns by analyzing astronomical information. For example, mathematical equations can be used to determine the position of celestial bodies and their influence on weather patterns.