Brian, zack, dan, jay, ed, and andrew want to play a two-player video game. if only two people can pay at a time, how many different pairs can they form for the first matchup?

a 12
b 36
c 15
d 30

Afootball quarterback has two more chances to throw a touchdown before his team is forced to punt the ball. he misses the receiver on the first throw 25% of the time. when his first throw is incomplete, he misses the receiver on the second throw 15% of the time. what is the probability of not throwing the ball to a receiver on either throw?