The total revenue for Jane's Vacation Rentals is given as the function R(x)=400x−0.5x2, where x is the number of villas filled. What number of villas filled produces the maximum revenue

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?