A train blows its horn as it approaches a crossing. A.) if the train engineer observes a frequency of 125Hz and a stationary observer at the crossing observes a frequency of 132Hz, what is the speed of the train? (The speed of sound is 330m/sec on this day). B.) what frequency is observed by the person at the crossing as the train moves away?

Question

A train blows its horn as it approaches a crossing. A.) if the train engineer observes a frequency of 125Hz and a stationary observer at the crossing observes a frequency of 132Hz, what is the speed of the train? (The speed of sound is 330m/sec on this day). B.) what frequency is observed by the person at the crossing as the train moves away?  
 
Divide velocity by wavelength for frequency/ speed??? #8179081423 text if available when done please.

Damon · Answer

http://hyperphysics.phy-astr.gsu.edu/hbase/Sound/dopp.html