An airplane is traveling at 150 km/h in a horizontal line on its way to drop emergency supplies to a group of flood victims 200 m below. The supplies should be dropped how many seconds before the plane is directly overhead?

An important dimensionless parameter concerned with very high-speed flow is the mach number, defined as v/c, where v is the speed of the object such as an airplane or projectile, and c is the speed of sound in the fluid surrounding the object. for a projectile traveling at 1170 mph through air at 50 ˚f and standard atmospheric pressure, what is the value of the mach number?