how is differential calculus used?
It is used to study the behavior and evolution of different mathematical functions (which can replicate many natural and physical phenomenon) at different points
What's a basic use of statistics?
To effectively summarize and show major descriptive characteristics of a large pool of subjects
What's the fundamental role of finance?
Finance helps provide people/companies with loans to pursue business expansion and activity and also then disseminate the risk of the loan to the people/companies who have excess savings and are looking for return on their money.