In 1920, after returning from Army service, he produced a successful model and in 1923 turned it over to the Northeast Electric Company of Rochester for development.
The core of a star must be at the temperature of 10,000,000 degrees Celsius for hydrogen fusion to begin.
I believe that a light bulb releases visible light and a radio antenna releases a radio waves
Answer:
the distance between the submarine and the ocean floor is 11,250 m
Explanation:
Given;
speed of the wave, v = 1500 m/s
time of motion of the wave, t = 15 s
The time taken to receive the echo is calculated as;

Therefore, the distance between the submarine and the ocean floor is 11,250 m
The correct answer is D, Diamond