Determining the resistor value to dissipate energy in inductive and capacitive components in the circuit
In the context of your assignment, what you need to do is to make and state some assumptions, and then model what you have assumed.

For instance, you could make the following assumptions - zero impedance mains, lossless components, open circuit filter. This would result in a very bouncy response, as the only dissipative element is R1, which is there just to discharge the capacitors when the circuit is disconnected.

Or you assume the same conditions, but with a 1 amp lamp load of 240 ohms loading the output, or 5 amps.

Or you could model it with a perfect rectifier/capacitor load drawing an average of 1 amp, or 10mA, or 10A.

Or you could model a lossy K1 (look at some commercial filters, some will tell you what their loss is) with some resistance in series with it.

Or with the rectifier load, model some intrinsic series diode resistance, and some electrolytic capacitor ESR, they will all absorb energy and tame the response, and perhaps a sniff of mains impedance, a fraction of an ohm.

Or you could do all of those, and compare and contrast the frequency responses. That will get you the most bonus marks, and the most understanding.