Response to the following problem:
The differential amplifier of Fig. is measured and found to have a short-circuit transconductance of 2 mA/V. A differential input signal is applied and the output voltage is measured with a load resistance RL connected. It is found that when RL is reduced from ∞ to 20 kΩ, the magnitude of the output signal is reduced by half. What do you estimate Ro and Ad (with RL disconnected) to be?