Final answer:
The activity variance, calculated by subtracting the actual revenue from the flexible budget revenue, is a $5,000 unfavorable variance (U) because the actual revenue was $5,000 less than expected.
Step-by-step explanation:
The performance report provided shows that the planning revenue was $240,000, the flexible budget revenue was $225,000, and the actual revenue was $230,000. To find the activity variance, you compare the flexible budget revenue with the actual revenue. The formula is Flexible Budget Revenue - Actual Revenue = Activity Variance. In this case, the activity variance is $225,000 - $230,000, which equals a $5,000 unfavorable variance (U). This means that the actual revenue was $5,000 less than what was expected from the flexible budget.