Vilfredo Pareto, the author of the 80/20 rule, observed this rule to be in effect in both _____ and _____.

Select an answer:
fishing; the stock market
real estate; gardening
gardening; spelunking
eating; blinking

real estate; gardening

Vilfredo Pareto, the author of the 80/20 rule, observed this rule to be in effect in both real estate and gardening.

To find the answer to this question, we can start by understanding what the 80/20 rule, also known as the Pareto Principle, states. The 80/20 rule suggests that roughly 80% of effects come from 20% of causes. In other words, a small percentage of inputs or efforts typically yield a large percentage of results.

Next, we need to determine which activities were observed by Vilfredo Pareto to adhere to this rule. Since Vilfredo Pareto was an economist, we can infer that he focused on economic activities. Among the given choices, the only option related to economic activities is "fishing" and "the stock market."

Therefore, the correct answer is: fishing; the stock market.