It can either be all of them or just 1 and 3
<span>The radio frequency characteristic that best determines the range of a 2.4 GHz ism signal is the wavelength.
This frequency can be used in WiFi and can reach up to 46 meters when indoors and about 92 meters when outdoors.
</span><span>
</span>
THE DOPPLER EFFECT. Anyways, it would have a higher whistle as it approaches you, when it gets to you it only gets quieter because it leaves after. Think of a motorcycle going by, its loud coming to you then as it passes it gets quieter.
First think which has less mass in the solar system. The sun is the largest object in the solar system, so the answer is C. the sun. Hope I helped! :P