The amplitude of a signal grows linearly with slope 5 and y-intercept 8. If the signal has frequency 5 and is shifted to the right 15 compared to a nearby radio wave, determine a function f(t) that describes the signal. a. f(t)=(5t+8)cos(15(t-5)) b. f(t)=(8t+5)cos(5(t-15)) c. f(t)=5cos(5(t-15))+8 d. f(t)=(5t+8)cos(5(t-15))

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