Awheel makes 282 revolutions per minute. how many revolutions does it make per second

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?

In the given figure ar(adf) =ar(cda) and ar(cdf) = ar(cdf). show that abdc and cdfe are trapeziums.

Which one ? is the answer and how to find this answer