Explanation:

Let’s break it down:

- Wealth (): This is definitely a stock concept. Wealth measures the total value of assets (like cash, property, investments) that you have at a specific point in time. Think of it as a snapshot of what you own right now.

- Saving: This is a flow concept, not stock. Saving is the amount you add to your wealth over time – like money you set aside each month.

- Export: Another flow. Exports count the value of goods and services a country sells to others over a period, not at a moment.

- Profit: Also a flow. Profit is the income leftover after expenses, but again, it’s measured over time, not in one instant.

So, among these, only wealth is a stock variable. The rest are all about change over a period.