Answers to question P:

  a)  under-damped

  b)  x(t) = A cos(omega*t + phi) e^(-t/tau)
          or
      x(t) = A cos(omega*t) e^(-t/tau)  +   B cos(omega*t) e^(-t/tau)

  c)  omega = 4.8967  rad/s

  d)  period = 1.2832  s

  e)  using the first form of the general solution, 

        x(t)  =  (-2.5033 m) cos( [4.8967 rad/s]*t + 0.05101 rad) e^(-t/6.667 s)

  f)  look at the file 
           http://spiff.rit.edu/classes/phys283/prac/prac_t1/prob_p.png
        or, for a rough sketch,

                                                                               
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   -1 |**....*..*...:.*..*.....****.....***....:..*..........:...........+-|   
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