Send wave from your location to the object and wait until echo is back.
Measure the time taken.
If you know the speed of wave (say sound wave), than just multiply by half time taken wave to return
Answer:
Light comes in different colors like radio, ultra violet, gamma-ray, etc, and they are invisible to the bare eye
Explanation:
I would say your answer is B- Some of the chemical energy from the batteries is converted into heat energy.
People are resistant to change, People have political freedom, Farmers institute new farming techniques and there is little need for medical facilities.
