Question 319696
You didn't specify a temperature or altitude to determine the speed of sound.
I'll use 700 mph as the speed of sound.
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Frequency
The equation for the observed frequency of sound when the source is traveling toward you is:

fo = fv/(v − vt)

where

fo is the observed frequency 
f is the emitted frequency 
v is the velocity of sound 
vt is the velocity of the source toward you 
v > vt (vt is less than v)
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fo = 1500*700/(700 - 80)
fo =~ 1694 Hz