Hurry please at a grand opening sale 20% of the first of 500 customers won a prize. How many of the first 500 did not win a prize?

Would greatly appreciate these 3 answers

Fracisco's game involves 3 green, 2 yellow, 4 red, and 3 black marbles. if he randomly draws three marbles from the bag, without replacement, what is the probability that he will draw yellow, and then red, and then black? a)1/192 b)1/72 c)3/220 d)1/55

Angle m aoc=108° m aob=3x+4° m boc=8x-28° find m aob