What is the most amount of time (in minutes) for a signal from the Mars Rover to reach Earth? (This is when Mars and Earth are farthest apart at 401 million km.)

What is the frequency of infrared light of 1.0*10^-4 wavelength?

Compute the wavelength of the radio waves from the following stations. (a) an AM station operating at a frequency of 780 kHzm(b) an FM station with a frequency of 96.9 MHzm

While passing between Earth and the Moon, a spacecraft is momentarily located on the line connecting the centers of the two bodies and is at a distance of d = 166 km from a radio antenna on the surface of Earth. The distance from the antenna to the moon is denoted by dm.   (b)  Scientists on Earth send a command to the spacecraft, which immediately sends back a receipt confirmation signal. How long, in seconds, after the scientists send the command does it take before they learn it was received?   (c)  Scientists bounce a laser beam off the Moon and measure the two-way travel time to be 2.42 s. How far away is the Moon in meters?