Can someone help me with this one!

How can we find the measure of an exterior angle if we know the measurement of an interior angle

What is the radical expression that is equivalent to the expression 27 1 over 5?

Which questions would most a reader identify the author's purpose for writing? check all that apply. what type of text is this? what type of reviews did the book receive? how many copies of the book have been sold? what is the central idea? how does this text make one feel?