What output would you expect in the inverting amplifier if Ri were open?

If the input resistor (Ri) of an inverting amplifier is open, the amplifier would not receive any input voltage. Consequently, the output would be undefined or could potentially swing to the positive or negative supply voltage, depending on any stray voltages or noise present in the circuit. Essentially, the amplifier would not function as intended, as it relies on a defined input signal to produce an output.