Physics help - Basic Wave Review Question?

I'm really stuck on this question for Physics: Melinda (a somewhat eccentric physics student) has her left ear against the concrete driveway. If someone drops a metal trash can onto the driveway about 30 m away, will she hear one sound or two? If two, which one arrives first? Any help would be appreciated :) show more I'm really stuck on this question for Physics:

Melinda (a somewhat eccentric physics student) has her left ear against the concrete driveway. If someone drops a metal trash can onto the driveway about 30 m away, will she hear one sound or two? If two, which one arrives first?

Any help would be appreciated :)
2 answers 2