A physical therapist at Enormous State Univeristy knows that the football team will play 40% of its games on artificial turf this season. He also knows a football player's chances of incurring a knee injury is 50% higher if a player is playing on artificial turf instead of grass. If a player's probability of knee injury on artificial turf is .42, what is the probability that
a.) A randomly selected player incurs a knee injury?
b.) A randomly selected player with a knee injury incurred the injury playing on grass?
Please show and explain work
a.) A randomly selected player incurs a knee injury?
b.) A randomly selected player with a knee injury incurred the injury playing on grass?
Please show and explain work