This speaker is part of Rice's Orwellian public announcement system. Assume it emits a spherical wave at 300 Hz that travel at 343 m/s. Your head is 51.20 m from the speaker. Your friend is walking behind you and his head is 51.835 m from the speaker. What is the difference in phase between the sound waves that you hear and your friends hear in degrees

This question is incomplete and not physics but i'm  willing to if you can give a better question

Stars are born within the clouds of dust and scattered throughout most galaxies. a familiar example of such as a dust cloud is the orion nebula. turbulence deep within these clouds gives rise to knots with sufficient mass that the gas and dust can begin to collapse under its own gravitational attraction. as the cloud collapses, the material at the center begins to heat up. known as a protostar, it is this hot core at the heart of the collapsing cloud that will one day become a star. three-dimensional computer models of star formation predict that the spinning clouds of collapsing gas and dust may break up into two or three blobs; this would explain why the majority the stars in the milky way are paired or in groups of multiple stars.therefor, i would say the answer is: dust and gases contract.i hope this ! < 3

Ibelieve it would be ddt

En espanol amigo por favor