Why does math get so hard that you have an answer but you forget what your answer was because it was so so so so so so so so so so so so so so hard. Why is it hard?

Which of the following should be considered when evaluating the credibility of a text based on the voice? whether the voice is masculine or feminineo whether or not there is biaso whether or not the voice is true to the author's actual personalitywhether or not the voice reveals the timeline of the text