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Thevenin and Norton Equivalent

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Question:

The way we measure the Thevenin & Norton Equivalent of a circuit is to look at the
open-circuit voltage, Voc = Vt, and short-circuit current, Isc = In. The Rt and Rn can
then be found using Ohm's law:
Rt = Rn = (Voc/Isc)

In a practical application, a more realistic model of an Ammeter and a Voltmeter are
shown in the figure below. The internal resistances, rm, on the Ammeter is in the order
of rA ˜ 0.1[Ω] and for the Voltmeter is in the order of rV ˜ 1[MΩ].

For a given circuit (unkown network), measurements (using the realistic instruments) of
the open-circuit (Thevenin) voltage gives Voc = 10.00[V], and the short-circuit (Norton") current gives Isc = 0.100[A].
a) Evaluate the apparent resistance, Rapparent, using the formula above (eq. 3) with
the apparent "voc" and "isc".
b) Estimate the actual equivalent resistance, Thevenin Voltage and Norton Current
taking into account the internal resistances of the sensors, rA, and rV.