Answer : First of all, to harness the solar energy and utilize it for the decomposition of water to make hydrogen fuel cell seems to be easy but practically it has many hurdles in its way. It might not work well, when the days would not be sunny. Also, the production of hydrogen fuel would require decomposing water which may need a high energy of activation, which would be more than the energy that will be produced from the fuel cell.
Answer:
89.45 v/v
Explanation:
Let's take the data:
First draw the amplifier circuit.
After the circuit, the voltage division rule can be used to compute the parameters:
The input section is computed like this: 
The output section is computed like this 
The product A
gives
A
= A×
×
Computing gives output voltage = 89.45 v/v
He should a step-up transformer with k=220/120=1.83 so output coil must have 240*1.83=440 turns
Answer:
I would love to help, Could you put the question in English?
Explanation: