4. The topmost photograph above shows the shock waves around a model of the X-15 experimental aircraft being tested inside a wind tunnel. The bottom photograph above shows the shock wave and air turbulence from a bullet immediately after it has been fired from a rifle. Assume both photographs were taken near sea level and at room temperature. a) Estimate how fast the air is passing by the model of the X-15. b) Estimate the speed of the bullet.

4. The topmost photograph above shows the shock waves around a model of the X-15 experimental aircraft being tested inside a wind tunnel. The bottom photograph above shows the shock wave and air turbulence from a bullet immediately after it has been fired from a rifle. Assume both photographs were taken near sea level and at room temperature. a) Estimate how fast the air is passing by the model of the X-15. b) Estimate the speed of the bullet.