Two trucks travel at the same speed. they are far apart on adjacent lanes and approach each other essentially head-on. one driver hears the horn of the other truck at a frequency that is 1.05 times the frequency he hears when the trucks are stationary. if the speed of sound is 344 m/s, at what speed is each truck moving?

this is how i worked it out but i got it wrong..

f=1.05hertz
1.05*f1=f1 (344+v1) / (344-v1)

(344-v1)*1.05 = (344+v1)
361.2-1.05v1= (344+v1)
361.2-344= 17.2
17.2=1.05v1
16.4m/s

The dipole moment of the water molecule (h2o) is 6.17x10^-30 c. m. consider a water molecule located at the origin whose dipole moment p points in the +x-direction. a chlorine ion ( of charge-1.60x10^-19c , is located at x=3.00x10^-9m . assume that is much larger than the separation d between the charges in the dipole, so that the approximate expression for the electric field along the dipole axis can be used. a) find the magnitude of the electric force that the water molecule exerts on the chlorine ion. b) what is the direction of the electric force. -x-direction or +x-direction c) is this force attractive or repulsive?