First, thanks for the tremendous help.

For this question I think you got the first and the second part wrong, I couldn't find why for the first part, but for the second part you changed the dumping and I think this what changed the final answer the right answer is 0.915 mm which is in the back of the book. part b asked you to change the stiffness only and leave the damping and mass without change.

Thanks again for the help ]]>

thank you ]]>

for part a, particular solution should be 2.5*(10^3)/wn^2 . am I correct?

Thank you. ]]>

You will need to use the homogeneous and particular response to find the amplitude.

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