D for sure. Just like how the ground rises over millions of years.
<span>1. A hydrogen fuel cell is more efficient than a combustion reaction because very little of the released energy is released as HEAT.
We need more energy emit as light and less heat. Lesser the heat more the efficiency.
2. </span>when used at home a fuel-cell illuminates the need for <span>an electrical grid</span> because the cell is portable.
As said, it is portable.
Answer:
A
Explanation:
The Sun doesn't move but the moon rotates around the earth making it so that the moon is always receiving different fractions of sunlight at different times. For example,
SUN. EARTH. MOON
︵
( ) O •
‿
as you can see, there is no sunlight hitting the moon._.
if you mean the same part of the Moon, the answer is still A because the Moon rotates and is always at a different spot
Usually during exercise, unlike during rest times the muscle cells need to respire more. So they need more oxygen and glucose for energy and the carbon-dioxide produced as waste must be removed quickly. So when person gets tired or breathes heavily during intensive workouts means they are in need of more oxygen. So the cells starts performing anaerobic(lactic acid ) respiration even though it releases less energy.
