Answer:
11%
Step-by-step explanation:
The computation of the annual rate of return is shown below:
Annual rate of return = Average annual income ÷average investment 
where, 
Average investment = (Initial investment + Salvage value) ÷ 2 
= ($284,000 + $74,000) ÷ 2 
= $179,000 
 And, 
Average annual income is 
= $60,490 - $40,800 
= $19,690 
 So, the annual rate of return is 
= $19,690 ÷ $179,000 
= 11%
We simply applied the above formula