[填空题]
How fast is an objech w5s4jm;qzgle6vf: 27q ;(0 oc/8fz:-r7l5ptyawynjj hz eht moving on land if its speed at 20 $^{\circ} $C is Mach 0.33? m/s
(b) A high-flying jet cruising at 3000 km/h displays a Mach number of 3.2 on a screen. What is the speed of sound at that altitude? m/s
