Answer:
$3
Step-by-step explanation:
Given parameter: 
Selling price of the radio = $41.81 
Sales tax = 7% 
Unknown: 
Tax incurred = ? 
Solution: 
The sales tax on the radio can found by; 
 Sales tax = % Sales tax x selling price of the radio 
 Sales tax = 7% x $41.81 
 Sales tax = $3