Bats emit sounds of frequencies around 35.0 kHz and use echolocation to find their prey. If a bat is moving with a speed of toward a hovering, stationary insect,
(a) What is the frequency received by the insect if the air temperature is 20 oC?
(b) What frequency of the reflected sound is heard by the bat?
(c) If the insect were initially moving directly away from the bat, would this affect the frequencies? Explain.