Serviceability: Analyze the performance of the deisgn (BJT Amp for the highest common mode rejection ratio) when the most critical resistor value changes by +/- 5%.

Can you breakdown how to perform this. Is it as simple as increasing/decreasing the crictial resistor value by 5% of its ideal value within the circuit?

i.e. critical resistor value. Rc=10k ohms.

would i use: Rc=10.5k ohms and Rc=9.5k ohms for the +/- 5% (creating two different circuit analysis'?)

utilizing ltspice for analysis.