15.00 x (1 - 30/100)
= 15.00 x 0,7
= 10.50
The sale price is $10.50
        
             
        
        
        
The option that will prove that the author was subjective at a time is the one that reflects his personal opinion on the matter.
<h3 /><h3>What is a Subjectivity?</h3>
Subjectivity refers to the channeling of a personal opinion. Someone who is subjective might be guided by his emotions. Such a person does not arrive at conclusions with facts. 
So since the options were not provided, the right one has to show the author's personal feelings.
Learn more about subjectivity here:
brainly.com/question/17971191
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