Which of the following polygons is not a regular polygon?

The longer leg of a 30° 60° 90° triangle is 16 times square root of three how long is a shorter leg

Are the corresponding angles congruent? explain why or why not.

60 musicians applied for a job at a music school. 14 of the musicians play both guitar and drums, 28 play drums, 18 play the guitar. what is the probability that the applicant who gets the job plays drums or guitar?