Profit

question 21

Multiple Choice

Profit

• A)Is the difference between total revenue and total cost.
• B)Is the difference between variable costs and fixed costs.
• C)Is always a number greater than zero.

---

Definitions:

Alveoli

Tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide takes place during breathing.

Oxygen

A chemical element vital to most life forms on Earth; it is a key component of the air and is crucial for cellular respiration.

Diffusion

Diffusion is the passive movement of molecules or particles from regions of higher concentration to regions of lower concentration until equilibrium is reached.

Hypertonic

A hypertonic solution has a higher concentration of solutes compared to the inside of a cell, causing water to move out of the cell and leading to cell shrinkage.