$1)$ Consider the commercial InGaAs, $\backslash (\backslash$mathrm$\{$Ge$\},\backslash$mathrm$\{$Si$\}\backslash )($Enhanced and Conventional$)$ pin photodiodes. The responsivity curves are given in the figure below.

a$)$ For each photodiode, find the

$\backslash ($ R$($A$)\backslash )$ power at $1550$ nm that will give a photocurrent of $10$ nA $.$ Comment on the answers.

b$)$ What would be the QE for each photodiode in part $($a$)?$ Comment on the answers.

c$)$ For each photodiode, for the same optical power in part $($a$),$ find the photocurrent at $1064$ nm $.$

d$)$ Plot the QE of the InGaAs pin photodiode versus wavelength. Comment on the figure.