Describe the roots of the equation shown below.

3x^2-10x-5=0

a. there are two real, irrational roots.
b. there is one real, double root.
c. there are two real, rational roots.
d. there are two complex roots.

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.