Each of Problems 15 through 18 gives the parameters for a forced mass-spring-dashpot system with equation mx" + cx' + kx = F₀ cos ωt. Investigate the possibility of practical resonance of this system. In particular, find the amplitude C(ω) of steady periodic forced oscillations with frequency ω. Sketch the graph of C(ω) and find the practical resonance frequency w (if any).

m = 1, c = 6, k = 45, F₀ = 50