To calculate the total earnings of the worker before going on vacation:
- The worker earns $10 per hour.
- The worker works 10 hours a day.
- The worker works for 10 days.
Total earnings can be calculated as follows:
\[ \text{Total earnings} = \text{hourly wage} \times \text{hours per day} \times \text{number of days} \]
Substituting the values:
\[ \text{Total earnings} = 10 , \text{(dollars/hour)} \times 10 , \text{(hours/day)} \times 10 , \text{(days)} = 10 \times 10 \times 10 = 1000 , \text{dollars} \]
This can also be expressed as \(10^3\).
Therefore, the answer is:
\(\mathbf{10^3}\)