how long would it take a radio wave with a frequency of 4.3 X10 to the 5th power Hz to travel from Mars to Earth if the distance between the two planets is approximately 8.00 x 10 to the 7th power km?

To determine how long it would take a radio wave to travel from Mars to Earth, we need to use the formula:

Time = Distance / Speed

First, we need to convert the given distance from kilometers to meters. Since 1 km = 1000 m, we have:
Distance = 8.00 × 10^7 km * 1000 = 8.00 × 10^10 m

The speed of a radio wave in a vacuum is the speed of light, which is approximately 3 × 10^8 meters per second (m/s). Therefore, the speed of the radio wave is:
Speed = 3 × 10^8 m/s

Now, we can calculate the time it would take for the radio wave to travel from Mars to Earth:
Time = Distance / Speed
= 8.00 × 10^10 m / (3 × 10^8 m/s)

To simplify, we can cancel out the powers of 10 in the numerator and denominator:
Time = (8.00 / 3) × (10^10 / 10^8) s
= 2.67 × 10^2 s

So, it would take approximately 267 seconds (or 2 minutes and 47 seconds) for the radio wave with a frequency of 4.3 × 10^5 Hz to travel from Mars to Earth.