Consider the following premises. If it is cloudy, then Patricia is a musician. For all x_15, x_15 is not a musician. It is cloudy if and only if William is playing tennis. If William plays tennis, then David is playing a game. If David plays a game, then William is playing tennis. Can we infer the following from them? David is playing a game.
 From the fact that if William plays tennis, then David is playing a game, and that if David plays a game, then William is playing tennis we can infer that William is playing tennis if and only if David is playing a game. From the fact that for all x_15, x_15 is not a musician we can infer that Patricia is not a musician. From the fact that if it is cloudy, then Patricia is a musician, and that Patricia is not a musician we can infer that it is not cloudy. From the fact that it is cloudy if and only if William is playing tennis, and that it is not cloudy we can infer that William is not playing tennis. Finally, from the fact that William is playing tennis if and only if David is playing a game, and that William is not playing tennis we can infer that David is not playing a game, which contradicts that David is playing a game. Therefore, the answer is no.