The behavior of a sound wave is affected by the density of the medium, the temperature of the medium and the pressure of the medium if it is a gas. Motion of the medium independent of the sound wave may also affect the way sound propagates.
Yes, you may check-in for your Delta Air Lines (DL) flight with your mobile device starting 24 hours and ending 60 minutes before the scheduled departure time (depending on your departure city and destination) to receive a mobile boarding pass on your mobile device.
Check-in for your flight right from the comfort of your home or office by visiting the Delta Air Lines online check-in. With helpful flight information and great support, Expedia eliminates the hassle in planning your trip and helps you have a great travel experience.rack arriving and departing flights in real-time with Delta Air Lines flight status, get information on baggage allowance and fees, and view flight timetables based on your departure and arrival times.