Hello. You did not enter the text to which this question refers, which makes it very difficult to answer it exactly. However, I will try to help you in the best possible way.
As you showed that the word "author" in line 10 was used as a proper noun, we can consider that the same word in line 4 was used in a general way and did not specify an exact person. This is because proper nouns are terms used to specify something or someone, as the question states that the word "author" was not used with the same meaning in line 4, we can consider that this is the difference.
To Portuguese explorers<span>, </span>the southern coast of West Africa became known as<span> the</span><span>. Gold Coast. The Treaty of Tordesillas, signed in 1494. established a line of demarcation between territories controlled by Portugal and those controlled by Spain.
Quizlet.</span>
Rules for representation in three house legislature