I think its the mirror because condenser helps in allowing the amount of light to pass.
I think it would be solubility but I’m not sure
Explanation:
A nuclear fission reaction is defined as the reaction in which a heavy nucleus splits into small nuclei along with release of energy.
The given reaction is 
Now, we balance the mass on both reactant and product side as follows.
235 + 1 =
236 = 234 + x
x = 236 -234
= 2
So, now we balance the charge on both reactant and product side as follows.
92 + 0 = 
92 = 96 - y
y = 4
Thus, we can conclude that there are 2 neutrons and 4 beta-particles are produced in the given reaction.
Therefore, reaction equation will be as follows.

Yes, transfer of energy is known as an energy transfer
<u>Answer:</u> The correct answer is Option 4: U
<u>Explanation:</u>
Activation energy is defined as the energy that is given to a chemical system with potential reactants to produce products. It is represented as 
It is represented as the energy from the reactants to the activated complex.
Reverse reaction is defined as the reaction in which the products formed become reactants and leads to the formation of reactants back.
So, here, the activation energy of the reverse reaction is the energy between the products and the activated complex, which is represented as letter U in the given graph.
Hence, the correct answer is Option 4: U