Answer:
Oil
Explanation:
Since, unlike oil, source like wind, solar, water etc. come naturally we don't and can't replace them but when the viscosity in oil has been used up it must be change to allow the proper functioning of the machine.
Answer:
the first one is the answer from my research
Explanation:
It is the serous membrane
Answer:
13. is Option J) all of the above
and 14 I'm not completely sure but I think its option D.
D. Most of the energy that drives metabolism is supplied by ATP
