Answer:
270 sec . ( = 4 min . 30 sec . ) Explanation: Any radio wave is moving at the speed of light, regardless of the frequency, so the frequency should be superfluous information. The speed is light is close to 300 , 000 k m s I take the distance you are given, to be 8.2 ⋅ 10 7 k m (since 8.2 ⋅ 107 k m doesn't make good sense - it's less than 1000 km) i.e. 82 , 000 , 000 km.
Before we actually compute this, we can notice that this is a little more than half the distance of the earth from the sun (150 mill. km), a distance the light uses 500 sek. = 8 min 20 sec. to travel, so we should get about 4 1 2 min for the radio wave to reach Mars from the earth.
Actual calculation: 82 , 000 , 000 km/300 , 000 k m s = 820 3 s = 273.3 s As the distance is given with 2 significant figures, we round this off to 270 sec = 4 min 30 sec.
Explantation:
Hope this helps =)
