What is the speed of sound in air at 40°c?

355 m/s
307 m/s
331 m/s
239 m/s

This is not a good answer, because some one t o forgot to tell us the important temperature, and the given atmospheric pressure "at sea level" makes really no sense. In SI units with dry air at 20°C (68°F), the speed of sound c is 343 meters per second (m/s).

Jet streams are relatively narrow bands of strong wind in the upper levels of the atmosphere. the winds blow from west to east in jet streams but the flow often shifts to the north and south. jet streams follow the boundaries between hot and cold air. the earth's rotation is responsible for the jet stream as well.