Answer;
Activation energy
Explanation;
Activation energy is the least possible amount of energy (minimum) which is required to start a reaction or the amount of energy available in a chemical system for a reaction to take place.
Catalysts can lower the activation energy and increase the reaction rate without being consumed in the reaction. The lower the activation energy for a reaction, the faster the rate. Thus enzymes speed up reactions by lowering activation energy.
Answer : The correct option is, (B) 
Explanation : Given,
Mass of proton = 
Speed of proton = 0.93 c
Formula used for relativistic momentum of the proton is:
where,
p = relativistic momentum of the proton
= mass of proton
v = speed of proton
c = speed of light = 
Now put all the given values in the above formula, we get:
Therefore, the relativistic momentum of the proton is,
A megawatt is larger than a kilowatt. The scientific notation for kilo is 10 to the 3, meaning 1000. A mega is 10 to the 6, meaning one million. That means a kilo watt is a thousand watts, and mega is a million watts
C. The membrane is inside the cell wall. The cell wall surrounds the membrane.
