You need to monitor the long-term stability (drift within a few hours) of a 10 µW laser beam emitting at the wavelength

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You need to monitor the long-term stability (drift within a few
hours) of a 10 µW laser beam emitting at the wavelength of 1550 nm.
The diameter of the laser beam is approximately 1 mm. ) Explain how
the laser power can be measured and read into a computer. (Block
diagram of main components needed and/or explanation). b) Assume
you are supposed to build the setup for scientific purposes. One
device only, your time is limited, and the accuracy is important.
Find commercial components you can use, and estimate the costs of
the setup. c) How does it change your choice of components, if the
device is mass produced, for example 1000 pieces to be integrated
to a laser system sold to the industry?