1. The problem statement, all variables and given/known data How long would it take a radio wave whose frequency is 7.25 x 10^5 Hz to travel from mars to Earth if the distance between the two planets is approximately 8.00 x 10^7 km. 2. Relevant equations Don't know what to put here. 3. The attempt at a solution 7.25 x 10^5 / 8.00 10^9=9.0625 x 10^-5 Is that they right answer or am i doing this whole thing the wrong way?