Final answer:
Checks, cash through mail, and lockboxes represent cash management techniques, which are crucial for handling transactions in both physical and electronic forms in an economy.
Step-by-step explanation:
Checks received through mail, cash received through the mail, and lockboxes are all examples of cash management techniques. These are traditional forms of payment collection that focus on managing and processing physical payments efficiently. Although we live in an age where financial capital often moves through electronic transfers, these physical methods remain integral to handling transactions where digital options are unavailable or unsuitable. Payment systems, whether they are electronic or physical, are crucial for the exchange of goods and services for money or other financial assets within an economy.