a.) Microeconomics deals with "small picture" economics in the realm of business and government. Microeconomics is usually industry specific and may deal with things such as utility, wages, short run business decisions, opportunity costs, etc. Macroeconomics looks at "big picture" concepts such as GDP, government spending, inflation, and international trade. They each intertwine very often and are both important to understanding managerial economics.

b.) Mathematical economics and econometrics are both applied versions of economics that each requires rigorous understanding of math and statistics. Mathematical economics uses calculus mostly to make economic predictions. Econometrics is both math and statistics heavy and aims to understand correlations and causations in economics through regression analysis. For example, econometrics might run series of regressions to understand why gasoline prices go up during the summer months. Managerial economics suggests that successful businesses should employ people who understand the of economics for business decisions and model reading.

c.) Accounting, finance, marketing, personnel, and production are all heavily intertwined into managerial economics of businesses, and each business you will find typically has an accounting/finance department, marketing department, personnel department(human resources), and someone who oversees production. Each are crucial to business organization.