<span>A. Chemical energy to chemical energy</span>
Although X-rays have many benefits, they can be dangerous to human health because they are short wavelength, high frequency, with photons sufficiently energetic to damage DNA molecules.
<span>A message needs to be traveled to mars from earth.
Distance between Earth and Mars (given) s = 400 million km
Speed of light = 3.00—10^5 km/ sec
We know Velocity = distance / time => time = distance / velocity
Time taken t = 400 million km / 3.00—10^5 = 400 x 10^6 / 3 x 10^5 = 1333.3 sec
Time taken t = 22 min</span>
