Enter the appropriate abbreviations.

Suppose the first five terms of a sequence are 4, 5, 9, 27, 123. how could the next term in the sequence be generated?

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.

Asix-sided number cube is rolled twice. what is the probability that the first roll is an even numbe and the second roll is a number greater than 4?