Help with a logic question are they right?

so i did these questions and was wondering if they are right since it is and even problem there is no solution in the back to know if they are right. my answers are at the bottom.

let p,q, and r be the propositions

p: you get an A on the final exam.

q: you do every exercise in this book.

r: you get an A in this class.

write these propositions using p, q, and r and logical connectives.

a) you get an A in this class, but you do not do every exercise in this book.

b) you get an A on the final, you do every exercise in this book, and you get an A in this class

c) to get an A in this class, it is necessary for you to get an A on the final.

d) you get an A on the final, but you don't do every exercise in this book; nevertheless, you get an A in this class.

e) getting an A on the final and doing every exercise in this book is sufficient for getting an A in this class.

f) you will get an A in this class if and only if you either do every exercise in this book or you get an A on the final.

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