I think the answer should be 16 because 1×2^4=16
The answer is A, friction.
Friction is the force that resists movement, and that's why oil is used as a lubricant and why ball bearings are used for machines that need to move with very little friction(i.e. bike wheels, roller skates, fidget spinners)
Answer B is too vague
C will probably reduce efficiency greatly, but not specifically in a way that turns work into thermal energy.
D is the same as C, except that it places the blame on the person using the machine, not the machine itself.
Hope I helped clear it up for you :)
Answer:
C. You cross from the western to eastern hemisphere
Explanation:
I believe this is the most reasonable answer but the question is a little confusing. If it is asking how to travel through different ecosystems then C is the most reasonable as A would only change the temperature and sometimes change the weather. B would keep you underwater all the time and you can't really switch ecosystems unless you got out. D, your staying in one ecosystem when climbing a mountain.
Hope this helps :)
No idea about the scientific reasoning, but the leaves of the plant are where the most photosynthesizing has to happen. In order for the plant to get energy it has to absorb the most light. So it creates broad leaves. The reason they are green is because chloroplasts are green. I believe that the cells in the leaves have more chloroplasts so that they can catch more sunlight.<span />