A 45 kg machine is placed at the end of a 1.6 m cantilever beam of elastic modulus of 200 GPa and cross-sectional moment of inertia 1.6* 10-5 m. As it operates, the machine produces a harmonic force of magnitude 100 N Answer questions 3 and 4. 3. What is the equivalent stiffness of the beam A. 4.34*106 N/m C. 2.34*106 N/m E. 6.02*10 N/m B. 5.34*106 N/m D. 3.33*106 N/m 4. At what operating speed will the machine steady-state vibration amplitude be 0.2 mm? A. 195.2 rad/sec B. 188.0 rad/sec D. 150.1 rad/sec C180.4 rad/sec E. 202.2 rad/sec cof Fo