A. Science cannot answer philosophical questions. Philosophical questions could be described as rheoretical questions, such as "what is the purpose of life?" These questions' answers can very from person to person. Science answers questions such as "what is the boiling point of water?", or "what is the chemical structure of water? These are both questions that have the same answer, no matter who is asking them. You just have to have the ability to accurately measure and observe the things involved, or in this case, the temperature of the water when it starts to boil or whe different atoms in the water.
Let's examine the other questions.
B. science can answer only mathematical questions. As you saw in the explanation above, science can also answer other questions, as long as they have a definite answer that we can accurately measure.
C.Science can answer any questions. Again, we have already saw that science cannot answer philosophical questions, so science cannot answer any question.
D. Science can answer any difficult questions. As with the example of the chemical stucture of water, we can answer difficult questions with science. This may seem simple to you, but it would be very difficult if it was not already known!
20.4 21.3 are the correct answers
Electricity is added to recharge a battery. A third phosphate group is added to ADP to form ATP.
ATP or Adenosine triphosphate contains adenine, ribose and 3 phosphate groups.
ADP is converted to ATP by the following reaction:
ADP+Pi+energy⇄ATP
The analogy between battery and ATP can be explained as ATP is higher energy form and ADP is lower energy form like charged and uncharged form of the battery. When the terminal or third phosphate is removed from the ATP it becomes ADP and releases energy like a battery. The additional phosphate group when added to ADP forms the ATP molecule like the energy spent by the batteries are recharged by putting in additional energy. Here the additional energy is provided by the third phosphate group.
