If in a p–n junction, a square input signal of $10 \mathrm{V}$ is applied as shown 

then the output across $R_{\mathrm{L}}$ will be

The circuit has two oppositely connected ideal in parallel. What is the current following in the circuit?

In the diagram, the input is across the terminals $A$ and $C$ and the output is across the terminals $B$ and $D$, then the output is