### Fearless Felix's Fast Fall!

They call him Fearless Felix, and the name fits. For years, Felix
Baumgartner has been making spectacular sky dives (jumps with a
parachute). He has jumped off the world's tallest buildings, across the
English Channel, into a 600-foot cave, and more. Now, Baumgartner plans
to become the first skydiver to break the speed of sound!

Sometime later this year, he will jump out of a helium balloon at least 120,000 feet above Earth. He will "free fall" for about 5 minutes, then open his parachute, then take another 10 minutes to reach the ground. What will Fearless Felix's average speed be, in miles per hour, for the entire 15-minute fall? (Round to the nearest whole number.)

**ON YOUR OWN:**
Baumgartner's speed will be much faster before he opens the parachute.
Thirty seconds into the jump, he will break the speed of sound.
Research, online or in the library, how fast the speed of sound is.