An employee at a pet shop randomly selects a fish from a tank where there are 5 guppies, 4 platyfishes, and 3 rasboras. What is the probability that the selected fish is a platyfish? Enter your answer as a fraction, in simplified form, in the box.

Astudent draws two parabolas both parabolas cross the x axis at (-4,0) and (6,0) the y intercept of the first parabolas is (0,-12). the y intercept of the second parabola is (0,-24) what is the positive difference between the a values for the two functions that describe the parabolas