Answer:
 The return on total assets is closest to 21.57%
Step-by-step explanation:
The formula to compute return on total assets is shown below:
Return on total assets = Net income ÷ Average total assets
where, 
Net income = Net income + interest × (1 - tax rate )
 = $27,300 + 13,000 × (1 - 30%)
 = $27,300 + 9,100
 = $36,400
And, average total assets = (Opening balance of total assets + Ending balance of total assets) ÷ 2
= ($170,000 + $167,400) ÷ 2
= $168,700
Now put these values on the above formula.
So, return on total assets is equals to
= $36,400 ÷ $168,700
= 21.57%
Hence, The return on total assets is closest to 21.57%