What is the principal part of the underlined verb in the sentence?

so far, i have read 10 books this summer.

a.
past participle

b.
present participle

c.
past

d.
present

Adam posted in a thread about theoretical physics. in his post he refuted general relativity and cited a paper that was recently self-published by one person on her own personal website and had no references to other works in the field. which important question did adam not answer sufficiently when evaluating the cited paper?

Which statement best describes the type of appeal used in this public service advertisement? an emotional appeal is made by presenting a wide range of jobs for women. an emotional appeal is made by emphasizing the need for a peaceful approach. an ethical appeal is made by providing pictures of a variety of role models. a logical appeal is made by including words that explain the meaning of the poster.

What does manns conclusion in "coming of age in the dawnland" indicate about how the settlements and people of sixteenth-century new england reacted to the increasing presence of europeans?