Given that E is the midpoint of AB and also the midpoint of CD prove that angle 1 equals angle 2

Adam drew two same size rectangles and divided them into the same number of equal parts. he shaded 1/3 of one rectangle and 1/4 of the other rectangle. what is the least number of parts into which both rectangles could be divided into?

Sketch one cycle if the cosine function y=2cos2theta

If you are dealt 4 cards from a shuffled deck of 52? cards, find the probability that all 4 cards are diamondsdiamonds.