I believe the answer is B. BC/EF is in the same placement as well as the other letters in the answer.
The four scientific principles of sustainability are...
1. Reliance of solar energy
how much of the sun we reuse.
2. Biodiversity
When there is a large verity of species.
3. Nutrient Recycling
When a Population benefit from other populations.
4. Population control
When one type of population of species is to large.
Have a wonderful day
A.Hunyo 12,1898,sa Kawit Cavite
Answer: D) water
Explanation: When pure hydrogen is used as the fuel, the only by-products generated from the fuel cell are pure water and heat.
