i) R2 is the larger signal.
ii) When B is switched off, R1 is y = a cos ꞷt
IR1 = a2/2
R2 is y = a cos ꞷt
IR2 = a2/2
So, it can be said that R1 and R2 are the same.
iii) When D is switched off, R1 is y = a cos ꞷt
IR1 = 1/2 a2
R2 is y = 3a cos ꞷt
IR2 = 9a2/2
iv) Therefore, R1 indicates B when B is switched off and R2 indicates D is switched off.