Final answer:
The statement is true when the blank is filled with 'commission', which means the person is paid a set percentage of the amount charged to the customer.
Step-by-step explanation:
When you are paid a set percent of the flat rate charged to the customer, you are paid a commission. The statement 'When you are paid a set percent of the flat rate charged to the customer, you are paid a(n) blank' is True when the blank is filled with 'commission'.
For example, if you work in a job where the flat rate for a service is $100 and your commission is 10%, you would earn $10 from that service. This is similar to calculating the percentage change in your pay, such as when receiving a $2 raise on a $10 per hour job, which represents a growth rate of 20% ($2/$10).