PLS HELP PLS To what volume should 5.0 mL of an 2.0 M citric acid solution be diluted in order to obtain a final solution that is 1.50 M? Round to two significant digits.

What kinds of numbers have an odd number of factors?

He that is measured at 220° is a reflex angle. the opposite angle is obtuse. find the measure of obtuse .

Set $r$ is a set of rectangles such that (1) only the grid points shown here are used as vertices, (2) all sides are vertical or horizontal and (3) no two rectangles in the set are congruent. if $r$ contains the maximum possible number of rectangles given these conditions, what fraction of the rectangles in set $r$ are squares? express your answer as a common fraction.