ind the currents flowing in the circuit in the figure below. (Assume the resistances are R1 = 6 Ω, R2 = 12 Ω, R3 = 20 Ω, R4 = 15 Ω, r1 = 0.25 Ω, r2 = 0.5 Ω, r3 = 0.25 Ω, and r4 = 0.75 Ω.)

While standing outdoors one evening, you are exposed to the following four types of electromagnetic radiation: yellow light from a sodium street lamp, radio waves from an am radio station, radio waves from an fm radio station, and microwaves from an antenna of a communications system. rank these type of waves in terms of increasing photon energy.