Hey guys! I am stack at this problem and not sure how I have to proceed, in the first part, when it says find the matrix for that rotation , does it mean from Q to P? do I find that by writing a trigonometric function of that and put it in an augmented matrix form?

B part...no clue.., C) is ok, and D? I can't really relate the information given with what they say it might be useful..Any help , hints ,clues...whatever, will be greatly appreciated