The bat is squeaking at a frequency, $f_{\text{b}\text{a}\text{t}}=13\mathrm{.}5kHz,$ as it flies straight toward the kid. The kid is too scared to move, but she's screaming at frequency, $f_{\text{k}\text{i}\text{d}}=1298Hz.$

The truck is just sitting there, reflecting everything that hits it$,$ and the speed of sound in the air is $349\frac{m}{s}.$

Use the simplified $($quick$-$n$-$easy$)$ doppler shift formula for single or double doppler shifts, as needed.

ECHO OF THE SQUEAKS

The bat hears the echo of its squeaks reflecting off the back of the parked truck.

$($a$)$ The echo of the squeaks heard by the bat has $q,$

a single doppler shift a double doppler shift no doppler shift

$($b$)$ If the frequency of the echo that the bat hears is $336$ Hz lower than the actual frequency of the its squeaks, how fast is the bat moving?

$v_{\text{b}\text{a}\text{t}}=$

$($c$)$ The echo of the squeaks that the girt hears coming from the parked truck has $q,4.$

a single doppler shift a double doppler shift no doppler shift

$($d$)$ Find the doppler shift of the echo heard by the girl.

$f_D=$

$$