During a thunderstorm, Max saw lightning and then heard thunder, 5 seconds later. What would be different if the air had been warmer?
In a thunderstorm, one typically sees the lightning first and then hears the thunder at some point later. This is because light travels much faster than sound. Let's look at each of the possible answers in turn.
In order to see the lightning and hear the thunder at the same time, the thunderbolt would literally have to strike right next to you. Since we know that there were 5 seconds of time between the two events, we know that this is not the case.
The second choice is not possible. Since light travels much faster than sound, the thunder could not reach the person before the lightning.
The only two real answers to choose from are the last two. Sound waves travel faster in warmer air than in colder air. This is because the heat in warmer air gives the air molecules more kinetic energy to move around and carry the sound energy more effectively. So in warmer air, sound waves from thunder will travel faster. If they travel faster, then you will hear them sooner. So the correct answer is C. Although to be honest the difference in time would likely be too small for a person to actually observe.