Answer:
About 2.5 seconds.
Step-by-step explanation:
The speed of radio waves is 299,750 km/s whereas the distance between moon and earth is 384,400 km. By dividing speed of radio waves over the distance of moon and earth, we get 1.22 seconds of time from one side or in other words the person on the moon receives message in 1.22 seconds from the earth and the person on the earth receives a response from the moon in also 1.2 seconds so total time taken by the sender in receiving response from the moon is 2.5 to 3 seconds.