Answer:
"Definition" Matches with " given an explanation of the unfamiliar word right in the sentence".
"Inference" matches with " Provides the general sense of an unfamiliar word with the main Idea of a sentence or paragraph"
"Synonym" matches with restates the unfamiliar word with another familiar word.
"Antonym" matches with contrasts the unfamiliar word with an opposite.
You can’t use third person without saying it’s your own research , but you can say “ people conducted their own research on this topic “
Assuming we're just looking at this phrase, "learn'd" suggests that the astronomer studied to become intelligent in the astronomical field.
Explanation:
computer has made education easer
1)