Given that i(t) = 7 sin(450t - 45°) milliamperes where t is the time measured in seconds.(a) Maximum current in milliamperes:Maximum current is given by the amplitude of the sine function.i(t) = 7 sin(450t - 45°) milliamperesAmplitude = 7 milliamperesHence, the maximum current is 7 milliamperes.(b) Frequency in hertz:The formula for the frequency of an AC signal is given as f = 1/T, where T is the time period of the signal.The time period of the given signal is given by 450t - 45° = 2πSo, T = (2π) / 450Time period T = (2 * 3.14) / 450Time period T = 0.014 sNow, we can calculate the frequency as:f = 1/T = 1/0.014 f = 71.42 HzRounding to the nearest hundredth, the frequency of the AC signal is 71.42 Hz.(c) Phase shift in milliseconds:The phase shift of the AC signal is given by φ = θ / 2πf, where θ is the angle of the sine function, f is the frequency, and φ is the phase shift.θ = -45° and f = 71.42 Hz.φ = θ / 2πfφ = -45° / 2π(71.42)φ = -0.0001247 sRounding to the nearest hundredth, the phase shift in milliseconds is -0.00012 s.